Seat Back Brace Question

[Simon T.]

I'm making my own seat back brace, does the brace need to attach to the seat or just rest against it? I glanced through the GCR and couldn't find it.

[DoubleXL240Z]

9.3.41. SEATS
The driver’s seat shall be a one-piece bucket-type seat and shall be securely mounted. The back of the seat shall be firmly attached to the main roll hoop, or its cross bracing, so as to provide aft and lateral sup- port. Seats homologated to and mounted in accordance with FIA stan- dard 8855-1999, or FIA.Standard.8862-2009 or higher need not have the seat back attached to the roll structure. Seats with a back not at- tached to the main roll hoop or its cross bracing may not be mounted to the stock runners unless they are the FIA homologated seats specified in an FIA homologated race car. The homologation labels must be visible. Seat supports shall be of the type listed on FIA technical list No.12 or No. 40 (lateral, bottom, etc). Passenger seat back–if a folding seat, it shall be securely bolted or strapped in place.
Mounting structures for racing seats may attach to the floor, cage and or center tunnel. Seat mounting points forward of the main hoop, between the center line of the car and the driver’s side door bar and rearward of the front edge of the seat bottom are not considered cage attachment points in classes with limitations on the number of attach- ments.
A system of head rest to prevent whiplash and rebound, and also to pre- vent the driver’s head from striking the underside of the main hoop shall be installed on all vehicles. Racing seats with integral headrests satisfy this requirement.
The head rest on non-integral seats shall have a minimum area of 36 square inches and be padded with a minimum of one inch thick padding. It is strongly recommended that padding meet SFI spec 45.2 or FIA Sports Car Head Rest Material. The head rest shall be capable of with- standing a force of two-hundred (200) lbs. in a rearward direction. The head rest support shall be such that it continues rearward or upward from the top edge in a way that the driver’s helmet can not hook over the pad.

[kevin22]

I believe these are way under valued, I have always had one on every seat I drive. I believe the real benefit will be in a side impact to keep the seat straight. Also be careful not to mount to low where your heavier upper body could fold the seat around it in rear impact causing back damage. The first car I bought had welded in "home made" very low. I believe in a real hard rear impact, the aluminum seat would have folded around this thing and snapped me in two.

[Simon T.]

So I guess I need to drill through the seat to attach it.

Thanks for the posts!

[Greg Amy]

It's only a matter of time before one of these seat back braces is directly responsible for someone being crippled or killed.

FIA seats - you know, ones that are designed specifically for the purpose and tested to destruction? - don't use seat back braces. And there's a reason for that.

And we're worried about head and neck braces... <rolleyes>

[Simon T.]

Most FIA seats cost a lot more than a non FIA seat.

[JeffYoung]

Greg, as a tech inspector, let me ask you a few questions. Not looking for a formal opinon of course, just want to bounce some ideas off of you.

Seat in my car is an FIA seat (Sparco) with a bottom mount ONLY.

Been looking for another seat and settled on the Sparco PRO 2000, which is also FIA homologated and also bottom mount.

Now, as I read the above rule, the seat must meat the standard and be mounted the same way as set forth in the standard.

I've read the standards and they are not entirely clear on this. They seem to suggest only testing with seat brackets (which I don't want to use) but I don't believe that Sparco could have gotten the FIA sticker for the seat if the bottom mounts hadn't be tested as well.

Thoughts?

By the way, I fully agree with you on those spears in the back of seats. Composite seats aren't designed for that.

Simon, what I've read on FIA v. non-FIA is that FIA won't give approval to an alum seat like a Kirkey. The FIA thinking is that an aluminum seat is not as safe for a variety of reasons.

US thinking seems to be different; Nascar boys have been using versions of that seat, with many improvements, for years.

I've raced cars with Kirkeys and things feel fine, but after reading the standards and the testing required to get an FIA cert I would not feel comfortable owning a seat that was not so tested.

The idea that a back brace is a sufficient replacmeent for that esting is a bit spooky to me.

QUOTE=Greg Amy;317623]It's only a matter of time before one of these seat back braces is directly responsible for someone being crippled or killed.

FIA seats - you know, ones that are designed specifically for the purpose and tested to destruction? - don't use seat back braces. And there's a reason for that.

And we're worried about head and neck braces... <rolleyes>[/QUOTE]

[Z3_GoCar]

I beileve there was a SFR SM racer who broke some ribs on a seat back brace that was part of the cage that rested aginst the seat back. This would have been about 7-8 years ago.

[Simon T.]

Greg, as a tech inspector, let me ask you a few questions. Not looking for a formal opinon of course, just want to bounce some ideas off of you.

Seat in my car is an FIA seat (Sparco) with a bottom mount ONLY.

Been looking for another seat and settled on the Sparco PRO 2000, which is also FIA homologated and also bottom mount.

Now, as I read the above rule, the seat must meat the standard and be mounted the same way as set forth in the standard.

I've read the standards and they are not entirely clear on this. They seem to suggest only testing with seat brackets (which I don't want to use) but I don't believe that Sparco could have gotten the FIA sticker for the seat if the bottom mounts hadn't be tested as well.

Thoughts?

By the way, I fully agree with you on those spears in the back of seats. Composite seats aren't designed for that.

Simon, what I've read on FIA v. non-FIA is that FIA won't give approval to an alum seat like a Kirkey. The FIA thinking is that an aluminum seat is not as safe for a variety of reasons.

US thinking seems to be different; Nascar boys have been using versions of that seat, with many improvements, for years.

I've raced cars with Kirkeys and things feel fine, but after reading the standards and the testing required to get an FIA cert I would not feel comfortable owning a seat that was not so tested.

The idea that a back brace is a sufficient replacmeent for that esting is a bit spooky to me.

Well my seat isn't an aluminum it's either plastic or fiberglass it's a Sparco, not sure what model, but it's not FIA approved. At least there isn't an FIA patch on it.

[erlrich]

It's only a matter of time before one of these seat back braces is directly responsible for someone being crippled or killed.

FIA seats - you know, ones that are designed specifically for the purpose and tested to destruction? - don't use seat back braces. And there's a reason for that.

And we're worried about head and neck braces... <rolleyes>

I would never get into a car with one of those spears pointed at my back - that just scares the hell out of me. But I believe it is possible to design a brace that won't hurt you, and still accomplishes the purpose. The one in my car is made from a piece of 1-1/4" flat steel, bent into sort of a U shape (actually more like 5 sides of an octagon), with the ends mounted to tabs on the cross bar that are about the seat-width apart. I haven't tested it (don't really plan to), but the idea is that the brace will deform enough in an impact that it will both prevent injury (by allowing some movement) and help dissipate some of the energy of the impact. Needless to say it's a one-shot deal.

[JeffYoung]

That's a damn good idea actually.


I would never get into a car with one of those spears pointed at my back - that just scares the hell out of me. But I believe it is possible to design a brace that won't hurt you, and still accomplishes the purpose. The one in my car is made from a piece of 1-1/4" flat steel, bent into sort of a U shape (actually more like 5 sides of an octagon), with the ends mounted to tabs on the cross bar that are about the seat-width apart. I haven't tested it (don't really plan to), but the idea is that the brace will deform enough in an impact that it will both prevent injury (by allowing some movement) and help dissipate some of the energy of the impact. Needless to say it's a one-shot deal.

[Simon T.]

What exactly are these spear braces you all speak of?

I plan on making mine sort of wrap around the back of the seat snug like to give the back of the seat good support, there is already a mount welded to the cage, I'm using tubing that goes through that, bolted in, then the end of the tube with the wrap around metal welded to that, also adjustable at the mount on the main hoop if it needs to be adjusted. I've seen some with just a bar pushing against the seat are those what you all speak of?

[Greg Amy]

...I don't believe that Sparco could have gotten the FIA sticker for the seat if the bottom mounts hadn't be tested as well.
FIA publishes their list of approved seats, along with what type of mount with which they were certified. Here's the 8855-1999 list, for example:

http://argent.fia.com/web/fia-public.nsf/D7050711553B12ADC12575F60035B089/$FILE/L12_Approved_seats.pdf

If yours is on that list (and it should be) and it says both "lateral" and "lower", you can use either.


Most FIA seats cost a lot more than a non FIA seat.
So does a lifetime of living in a wheelchair and blowing through a tube to move around.


What exactly are these spear braces you all speak of?
It's not just the fact that many poorly-designed braces become spears upon impact, it's also due to the fact that any properly-designed seat has "give" - both laterally and longitudinally - to absorb a lot of the shock. If you get hit and the seat don't give, guess where all the shock is going to...? Yep: you.

Seat back braces are nothing but a very bad Band-Aid to accommodate poorly-designed seats that have illustrated a tendency to fail. In fact, they first came to the fore when we were still using factory seats in Showroom Stock cars, where the adjustable seat backs were breaking.

Use whatever seat you want - the "standards" required by SCCA are laughable - but don't think that a seat back brace is anywhere NEAR sufficient to give you a level of safety comparable to a proper race seat. In fact, I suggest it probably worsens the situation.

GA

[JeffYoung]

Greg, THANK YOU. This is exactly what I was looking for.

The standard itself doesn't mention what type of testing was done to get the homologation. This does.

Much appreciated.

[Simon T.]

FIA publishes their list of approved seats, along with what type of mount with which they were certified. Here's the 8855-1999 list, for example:

http://argent.fia.com/web/fia-public.nsf/D7050711553B12ADC12575F60035B089//L12_Approved_seats.pdf

If yours is on that list (and it should be) and it says both "lateral" and "lower", you can use either.


So does a lifetime of living in a wheelchair and blowing through a tube to move around.


It's not just the fact that many poorly-designed braces become spears upon impact, it's also due to the fact that any properly-designed seat has "give" - both laterally and longitudinally - to absorb a lot of the shock. If you get hit and the seat don't give, guess where all the shock is going to...? Yep: you.

Seat back braces are nothing but a very bad Band-Aid to accommodate poorly-designed seats that have illustrated a tendency to fail. In fact, they first came to the fore when we were still using factory seats in Showroom Stock cars, where the adjustable seat backs were breaking.

Use whatever seat you want - the "standards" required by SCCA are laughable - but don't think that a seat back brace is anywhere NEAR sufficient to give you a level of safety comparable to a proper race seat. In fact, I suggest it probably worsens the situation.

GA

Well for the time being I don't have much of an option. :shrug: lol

[Greg Amy]

Jeff, you're welcome.


Well for the time being I don't have much of an option. :shrug: lol
Then keep in mind the "intention" for seat back braces is to keep you safe and in place in case the seat back breaks/permanently deforms. Design it to spread the load across the back of the seat as much as possible (i.e., a plate, and use panhead bolts towards your back, not hex heads) and try to let it have some "give" (no real suggestions for that). - GA

[Simon T.]

Jeff, you're welcome.


Then keep in mind the "intention" for seat back braces is to keep you safe and in place in case the seat back breaks/permanently deforms. Design it to spread the load across the back of the seat as much as possible (i.e., a plate, and use panhead bolts towards your back, not hex heads) and try to let it have some "give" (no real suggestions for that). - GA

Cool I'll keep that in mind and when I have some spare money upgrade to an FIA seat. Thanks.

[Chip42]

And everyone owes a lot of gratitude to the CRB who DID NOT continue pushing STUPID and ILL CONCEIVED rules floated recently requiring a back brace on ANY seat, FIA or otherwise, unless it could be proven that the mounts used are the same PN as the mounts the seat was certified with, which is ONLY possible on seats conforming to FIA 8862-2009 (advanced racing seats) as listed on technical list #40. there's less than 20 of these. most FIA seats are homologated to 8855-1999, and listed on TL#12, specifying the TYPE of mounting used (lateral, lower) and nothing more.

in effect, it would have forced just about everyone to have back braces. if you think they are scary on a metal seat, try it on a composite, or worse, an entry level, steel-frame FIA seat with webbing through the back and seat floor.

a rare instane of safety rule restraint on behalf od the club. use FIA seats and avoid back braces for all of the good reasons above. even a well designed back brace is, to me, less desireable than a well designed and well mounted seat.

[JeffYoung]

And many thanks to Chip for pointing this issue out to me. I totally missed it in all the jibber jabbah.

[Tristan Smith]

And everyone owes a lot of gratitude to the CRB who DID NOT continue pushing STUPID and ILL CONCEIVED rules floated recently requiring a back brace on ANY seat, FIA or otherwise, unless it could be proven that the mounts used are the same PN as the mounts the seat was certified with, which is ONLY possible on seats conforming to FIA 8862-2009 (advanced racing seats) as listed on technical list #40. there's less than 20 of these. most FIA seats are homologated to 8855-1999, and listed on TL#12, specifying the TYPE of mounting used (lateral, lower) and nothing more.

in effect, it would have forced just about everyone to have back braces. if you think they are scary on a metal seat, try it on a composite, or worse, an entry level, steel-frame FIA seat with webbing through the back and seat floor.

a rare instane of safety rule restraint on behalf od the club. use FIA seats and avoid back braces for all of the good reasons above. even a well designed back brace is, to me, less desireable than a well designed and well mounted seat.


So does that mean that the seat mounting device is irrelvant on a 8855-1999 seat as long as the seat is mounted in the way it was tested (either laterally or lower)? And if that is the case, what is the issue with slider type rails then?

Because this whole seat mounting issue is starting to be a real pain in the ass.

[Greg Amy]

...what is the issue with slider type rails then?
I don't know the details, but I'm inferring that the CRB (or whomever) does not like the idea of using stock sliders. There's probably a back story on this, something like someone tried to use some crap that wasn't safe and a Tech guy bounced 'em, then the person leaned on the lack of guiding info in the GCR to get by. Purely my guess.

I've used stock sliders in Miatas; they fit well and are built well. But no longer...


Because this whole seat mounting issue is starting to be a real pain in the ass.Tell me about it. I'm not quite sure anymore how much flexibility in judgment I have in approving seat mountings, nor a clear idea on what my minimal responsibility is.

GA

[seckerich]

There are FIA approved sliders available.

http://www.discoveryparts.com/cgi-bin/store/commerce.cgi?cart_id=1297098034.166&product=seats_acce&pid=417

I have seen these after some serious hits in the GT cars and they are very strong. We replace them after a hit but they were in perfect shape. I know these were in the car when Jeff got rolled up the banking at Daytona. I use them in all my cars now.

[Tristan Smith]

There are FIA approved sliders available.

http://www.discoveryparts.com/cgi-bin/store/commerce.cgi?cart_id=1297098034.166&product=seats_acce&pid=417

I have seen these after some serious hits in the GT cars and they are very strong. We replace them after a hit but they were in perfect shape. I know these were in the car when Jeff got rolled up the banking at Daytona. I use them in all my cars now.


They are great, I am sure. But I would like to see the data that says they are any safer than many of the OEM type sliders out there.

[Chip42]

the issue with seat mounts has to do with the fact that there ere NO guidlines regarding HOW to attach a seat in the GCR. this has been addressed recently to state lateral/lower and no sliders (with caveats). still nothing about fastener strength of any sort of demonstrable mounting standards. seats HAVE come loose in incidents because of the lack of enforcable mounting rules and a lack of desire on some scrutineers to force competitors to do something that ISN'T in the GCR. ("It says FIA and that's good enough for me" was unfortunately more common than it should have been). the OVER reaction was the language that was defeated. the currentl language is a small step toward better mounting standards without going overboard on rear braces and the like.

sliders fail. maybe yours are awesome, but without something OBVIOUS that PROVES that, like an FIA homologation, there's no way to suppor tthat at tech (no amount of human jostling is going to show the weaknesses a high G loading wreck will expose). this means a lot of seats need to be remounted. it's a lot better than the alternative, and it's cheaper than your new HnR.

[Dave Gomberg]

There are FIA approved sliders available.

http://www.discoveryparts.com/cgi-bin/store/commerce.cgi?cart_id=1297098034.166&product=seats_acce&pid=417...
Those sliders are NOT FIA approved. Go to the Recaro web site http://www.recaro.com/en/product-areas/motorsport/service/brochures.html and click on the online brochure. Go to page 32. Note that they have four different fixed side mounts that have FIA approval. The Double Locking Runners do not have the FIA logo. Discovery Parts is incorrect (at best) or is trying to pass off something that is not true (at worst). Note that on their listing for these runners they say "fia".

Dave

[Knestis]

Those sliders are NOT FIA approved. Go to the Recaro web site http://www.recaro.com/en/product-areas/motorsport/service/brochures.html and click on the online brochure. Go to page 32. Note that they have four different fixed side mounts that have FIA approval. The Double Locking Runners do not have the FIA logo. Discovery Parts is incorrect (at best) or is trying to pass off something that is not true (at worst). Note that on their listing for these runners they say "fia".

Dave

So you're saying that the "Double Locking Runners" "for all racing shells" on that same page, as sold by Recaro, are not satisfactory because you can't see an FIA logo...? Really? None of their side brackets are stamped or marked in any way so they aren't legal for SCCA Club Racing either? My understanding is that as long as I'm using the hardware designed for the homologated seat, and mounting it by their established practices, it's covered.

K

[seckerich]

It always amazes me that most professional motorsports use something, it works well, and SCCA thinks we are all to F-ing stupid to use it properly. Most of the DP cars in GA as well as GT cars use this setup. SCCA will however spec every aspect of a cage with no testing where others accept "industry standard". :happy204: Great input Dave. Care to elaborate on what covered up item prompted this overreaction? I know but will be glad to let you clue us in.

[Greg Amy]

This is a sure way to get the rule changed - and I apologize to those that are thinking the same thing - but the new rule states:

Seats with a back not attached to the main roll hoop or its cross bracing may not be mounted to the stock runners unless they are the FIA homologated seats specified in an FIA homologated race car.
Notice my bolded part. There's nothing prohibiting non-stock runners/sliders from being used. I'm I'm just getting a major giggle about the "FIA homologated race car" part...

Yeah, I want to know the back story on this, too. I'm guessing it's because of someone being a d**k.

GA

[Chip42]

if the seat is mounted to a Car's factory sliders, it must be a homologated seat mount (I don't know if this even exists, a porsche 911 cup car, maybe?). An aftermarket slider that is NOT FIA approved is a grey area, but should be disallowed by the same logic I outlined above (earleir post). if the seat mount isn't marked, have some sort of proof that it is an FIA approved slider. sliders are not homologated with FIA seats on list 12 (8855-1999) and most likely not those to 8862-2009, which have specific mounts, possibly sliders, used during homologation and those part numbers being required for the homologation to be honored (by FIA). There is no FIA homologation for seat mounts themselves, and sliders are not said to be used in the common standard (8855-1999) so there's no "right" answer here.

A fixed mount has near zero requirements OTHER than it tie to the seat using the homologated bosses (side or bottom). THIS remains a potential problem, but if you and your scrutineer are comfortable with you sitting there, go ahead. if the mount is inadequate, it's your funeral.

you could argue all day about it, but there's a big hole in the rules about fixturing strength. stock sliders out, the assumption I feel is that aftermarket are to be FIA approved, but there's really no homoogation standard for that. so... yeah.

[seckerich]

You are correct. Much safer to have a plastic or fiberglass seat with a pole attached to the back and be perfectly legal to the rule as written by SCCA. At least it has bolts and washers through the stock sheet metal floor to kep it secure. We know that is much safer than a proper double locking, full wrap around slider. Classic.

[jumbojimbo]

...An aftermarket slider that is NOT FIA approved is a grey area, but should be disallowed by the same logic I outlined above (earleir post).

I'm not quite getting you.

Are you saying that by reasonable logic it would only make sense to not allow aftermarket sliders although it appears the GCR is not doing so?

Or are you saying that applying the GCR rule that logic says that aftermarket sliders are not legal?

Because there are two questions here. GCR Legal/Not legal and safe/not safe. I can't tell which one you are trying to answer.

I appreciate the value of the safe/not safe question, I just have trouble sometimes wading thru a bunch of those to get to the legal/not legal answer.

[Chip42]

I'm not quite getting you.

not safe is a back brace on a composite seat, with a mount fab'ed by the owner. some FIA seats have back brace mounts built in. These are safe, and in the case of Racetech, required to be in conformance to 8862-2009. Racetech is the only 1 out of 4 seat manufacturers on that list to homologate their seats with back braces. only about 10 8855-1999 seats were homologated with a back brace, all but 3 of those are Racetech (the others are GM and BMW, I might have missed one more). The rest are only lateral or lower mounting to an unspecified bracket.

not safe is a shotty mounting of the seat to the thin floorboard of a 50 year old production car using bolts and standard washers. or 10 years old. still too thin.

not safe is a lot of production car seat sliders being used to mount a racing seat. often this is more true if the sliders are modified.

the rules state no FACTORY sliders wihtouyt a back brace. this is a good start, I guess - the back brace requirement still needs to be eliminated for seats that aren't designed for it, and such seats need to be mounted appropriately or disallowed, period.

FIA does NOT homologate seat mounts EXCEPT those homologated WITH the seat to 8862-2009 (tech list 40). on the Recarro brochure page cited above, the specific models homologated with those seat mounts are called out under the bold "Recaro racing shells" (for what it's worth, the seat mount cited in the homologation is Recaro PN 7307802). so we are left with having to DECIDE, in a repeatable manner, if an aftermarket, adjustable seat mount is sufficiently strong for mounting a racing seat because the GCR does not address this (except by omission), nor does the FIA ( which I feel the GCR is pointing to for acceptance criteria based on wording that was in the proposed rules, and since stricken / not adopted).

Most if not all of the adjustable seat mounts offered by the seat OEMs for use in motorsports are more than sufficient, but other aftermarket sliders often times are not. ditto many (not all) car OE sliding mounts. without some sort of identification and testing, it's too friggin hard to say what's good enough, objectively. SCCA chose to not trust what came in the car, and anything else is fair game. I think the restriction should be tighter than that, and manufacturer should be evident at minimum, and be a manufacturer of note with FIA homologated product, OR a list of allowed sliding mounts needs to be generated to get around the issue.

STATIC mounting remains, to me, and issue because the specification in the GCR are too slim and inadequate for making a reasonable baseline standard for mounting strenght. all one needs to do is adapt some of the rules from seat belt mounting for this purpose (load spreading washers, minimum hardware grades, etc...) to make a big improvement to the rules as they stand.

I wrote a LOT of letters and did a lot of leg work (phone work) talking to a lot of seat manufacturers, resellers, and reps, taking measurements, and getting information to shoot down the back brace requirements as they were floated. what we have now is an imperfect rule thats a lot better than the potential alternative would have been (requireing back braces on any seat without FIA approved mounts, which don't REALLY exist).

my appologies, steve, if I came accross in support of a back brace bolted to holes drilled in a composite seat. I wouldn't waste time crash testing such a setup for fear of writing off an expensive dummy. it's a ludicrously bad idea, and rather than encouraged, it should disallowed outright.

the trouble here is that many club racers aren't building to GrandAm quality, or on a GrandAm budget. they might have a welder... and a few dollars, and oh shit, this rule just changed... oh, look - these mounts from APC fit my honda, easy button! ouch - I'm dead. there's a BIG technology and prep level variation in the padock. anyone who works tech (like steve, tGA, myself, many others) knows this very well. the rules have to address this to keep the unsafe out, and minimize arguments and subjective mistakes at the tech shed.

[Chip42]

Care to elaborate on what covered up item prompted this overreaction? I know but will be glad to let you clue us in.

I'd LOVE to know what you're talking about.

and that Recaro mount, even if it WERE homologated, could be argued under the current rules as only legal when paired to an 8855-1999 seat whcih was homologated using lower mounting - a small minority of the seats from that list.

again - the rules need to be made better by people who know WTF they are talking about (like you, steve), and I got the impression from the rules being floated last year that whoever's writing them DOESN'T have a clue. that mount, on a good 8855 seat, should pass muster. period.

[Knestis]

See, this is the kind of thing that drives me insane about how we approach safety. I go and buy the best bits I can find, spend real $$ with a reputable manufacturer with tons of motor sports experience, work hard to engineer their parts into my vehicle...

...and then someone who wants to write a self-enforcing rule obliterates my hard work and decision making. I'd be fine with a non-sliding bracket that was pop riveted to the floor but the proper stuff that goes in GT cars all over the world isn't OK...?

I got told at the ARRC that I couldn't mount my FIA shoulder harnesses the way the manufacturer describes, either.

Argh.

K

EDIT for Chip - the side brackets bolt to the sliders.

[seckerich]

We are on the same page Chip. The sliders that are used in everything from GA to Porsche Cup are full containment, double locking and meet the requirements as written today. They have approved side or bottom mounts for the seat spec bolted to them with the specified grade and size of hardware. Unless the seat manufacturer designs the back brace system with the seat it is dangerous and opens legal liability SCCA does not want to deal with. Where we really agree is how badly some seat systems are then mounted to the car. Yet they would be legal as Kirk mentions. I have seen enough to be confident in my setup. I even designed a full width , movable back brace in case the proposed rule went through. Glad it is not needed.

[Chip42]

EDIT for Chip - the side brackets bolt to the sliders.
yeah I know but a lot of seats could be bolted to the bottom mounts that are there and NOT homologated. I was thinking of that installation.

I'm glad we're all on the same page. I'll shut up now.

[Streetwise guy]

This is a question purely to satisfy my curiosity. I know in Canada FIA trumps all. The FIA cage rules have a very specific and practically incomprehensible set of instructions and drawings on how to mount your FIA seat. If you mount your seat using the FIA guidelines, and carry the rules with you to show the inspectors, would SCCA have to accept it, or does the SCCA consider itself the final authority on these issues?

Same question applies to cage construction.

[Dave Gomberg]

So you're saying that the "Double Locking Runners" "for all racing shells" on that same page, as sold by Recaro, are not satisfactory because you can't see an FIA logo...? Really? None of their side brackets are stamped or marked in any way so they aren't legal for SCCA Club Racing either? My understanding is that as long as I'm using the hardware designed for the homologated seat, and mounting it by their established practices, it's covered.

K
Nothwithstanding any deficiencies in the current wording in 9.3.41, please note the following correspondence (answer at top, question below).

Dave
--------------------------------------------------------
Dear Mr Gomberg,

Thank you for your email. The side mounts are specific to a couple of seats that they have been tested with for the FIA Homoligation, to ensure you get the correct side mounts you will have to match the seat model with the side mounts. If you are unsure please let me know which model of seat you have so that I can then let you know which side mounts are available for that model.

The double locking runners don't have an FIA Homoligation, all the products that we have with FIA Homoligation will have the logo with the product, or it will be stated in the description. If you have any questions please contact me.

Kind regards

Tom Hemus
Sales Coordinator
_______________

RECARO UK
Holly Farm Business Park
Honiley
Warwickshire
CV8 1NP

Tel: 01926 484111
Fax: 01926 484220
email: [email protected]
Website www.recaro.com (http://www.recaro.com/)



-----Original Message-----
From: Dave Gomberg [mailto:[email protected] ([email protected])]
Sent: 07 February 2011 22:23
To: info.gb
Subject: FIA seat mounts

Hello:

I have a question about Recaro racing seat mounts.

On page 33 of the "Seat Range" brochure available on the Recaro web site, there are four sidemounts that are accompanied by an FIA logo. One would reasonably assume that all these mounts are acceptable for the installation of an FIA homologated Recaro racing shell in a car to be raced with a sanctioning body that requires seats that are FIA homologated.

Also on that page is a "Double locking runners" assembly which has no FIA logo. My question is this: can this runner assembly be used with a Recaro FIA homologated shell and still meet the FIA requirements as established in either the 8855-1999 or 8862-2009 FIA standards?

Thank you very much for taking the time to answer this query.

Dave Gomberg

[Chip42]

but, per the GCR, they ARE legal.

to streetwise:
if you mounted your seat in accordance with FIA regs, it would pass SCCA inspection without documentation. our rules are pretty lax, only STOCK sliders are made to be braced by a back brace (unless it's a non FIA seat). For cages you had better meet the SCCA regs. I think the ONLY exception are porsche cup cars, specifically. I may be wrong there. the good news is that most (not all) FIA cages will meet the CGR requirements.

it's strange that "we" apparently think we are so much smarter than the FIA. we go back and forth between them and SFI, and it leads to a lot of inconsistancy, and some idiodicly restrictive rules for safety gear.

[Knestis]

Thanks for sharing that, Dave. It's worrisome since that's not what I understood when i purchased them but it is what it is. It's frustrating that every year that goes by, it's increasingly hard to do the right thing - and we haven't really addressed the root issues among those who throw crap together...

K

[lateapex911]

So, let me boil this down if I can.
I CAN: Mount an FIA seat to FIA side or bottom mounts (if the seat was tested with the ones I've selected) and bolt those to my sheet metal floor.

But I can NOT weld a cross car tube or box section or two from my roll cage to the tunnel (In IT) and attach with proper grade hardware recaro sliders that have been in use in Grand Am cup and ALMS for years?

IF that's correct, who's doing the logic tests for the ruleswriters?

yea yea yea, I know, "It's based on the advice of legal counsel".

[Chip42]

Jake,

you CAN mount an FIA seat in ANY fashion you like OTHER than to stock sliders. so the recaro etc... double locking bits ARE OK per 9.3.41.

you CAN have extensions from your cage to the tunnel to use for a seat mount - see 9.3.41, paragraph 2. even in IT/SS etc...

the only restriction for FIA seats (other than a back brace must be used with stock sliders) is that the bolts to the seat go into the homologated holes (lateral or lower) as some seats have both but only were homologated with one.

the problems some of us have with the rules are

1 - there are no minimum standards for propper mounting (thus the brackets pop-riveted to the floor example which is completely legal)

2 - aftermarket runners MIGHT be just as unsafe as stock, as there is no homologation standard for or list of approved sliding mounts. so some aftermarket, non race worthy part could be passed as it is not stock. This does not include most/all of those made by the major FIA homologated seat suppliers (OMP, sparco, racetech, etc...) but there's still no objective standard other than "not stock".

[Russ Myers]

how can stock be considered unsafe when they are crash tested to nhtsa and dot standards. I crashed a fiesta with a stock seat at road atlanta and had no problems what so ever.

Russ

[joeg]

Russ--Yes you are probably correct. I have no clue why a modern OEM seat would not work well in a race car (other than for its weight).

[seckerich]

And the fact that the factory seat mounts were attached to a seat structure that was engineered to give it extra strength. Most are single locking, and not full captive. Now you are attaching it to a carbon, fiberglass, etc. seat without that steel frame and it will not perform the same way. Not safe.

[lateapex911]

Jake,

you CAN mount an FIA seat in ANY fashion you like OTHER than to stock sliders. so the recaro etc... double locking bits ARE OK per 9.3.41.
OK, reading the GCR rule, it says "supports must be of the type listed on FIA tech list.....".
So, am I correct in deducing that I can use ANY support in ANY way, as long as I use the right type...side or lower as listed? And i can mount those to any slider other than the stock sliders or heck I can glue them to the floor with bubble gum, again, as long as I don't involve stock sliders, unless THEY are FIA listed as such??


you CAN have extensions from your cage to the tunnel to use for a seat mount - see 9.3.41, paragraph 2. even in IT/SS etc...
Thanks, I missed the new section on my first run though the new GCR.


the only restriction for FIA seats (other than a back brace must be used with stock sliders) is that the bolts to the seat go into the homologated holes (lateral or lower) as some seats have both but only were homologated with one.

the problems some of us have with the rules are

1 - there are no minimum standards for propper mounting (thus the brackets pop-riveted to the floor example which is completely legal)

2 - aftermarket runners MIGHT be just as unsafe as stock, as there is no homologation standard for or list of approved sliding mounts. so some aftermarket, non race worthy part could be passed as it is not stock. This does not include most/all of those made by the major FIA homologated seat suppliers (OMP, sparco, racetech, etc...) but there's still no objective standard other than "not stock".

OK, I'm with you...
Another Head and Neck rule. :shrug:
Again, to those reading who write the rules, you have to see how when we read these rules, and obvious limits are placed on one aspect of a system, yet the rest of the system is 'free', it makes placing ANY limits on any part of the system look, well, stupid. In this case it's "Must have a backbrace, can't use stock sliders, etc". but no mention of actual attachment, so, ergo it all CAN bolt to the floor using spit....it just makes little sense.

And sure, you can say, "Well, you're racers, you know how to properly mount a seat...". Yup, I do, but I also know how to use the best head and neck restraint, and I can get out of it in a nano second even though it requires more than one release, yet you won't let me use that one, I have to use an inferior one....so lets not play the "you're smart enough to figure stuff out" card.

[seckerich]

There is also no "FIA" or any other spec for the required back brace. :rolleyes: Even if required it can be of creative design so as not to endanger the drivers spine.

[Chip42]

it CAN be, but the easy button is one of the IO port type spears. lots of people who race would never assume something sold as safety equipment could actually make them less safe.

like using pipe insulation / pool noodles instead of energy absorbing, fire retardant roll bar padding. it can actually make a bad situation worse.

rules makers need to either LET people be unsafe, or enforce stuff that actually leads to safety.

[Simon T.]

I created a monster. lol

Good info in here!

[Bremsen]

Ok, see fire....have gas....will throw.

Both the SCCA and NASA rule books on using the FIA seat say they must be mounted in accordance with the FIA standard. My question is regarding the harness mount as the FIA standard/test procedure states the seat back must be a minimum of 150mm from the cage and harness must be mounted between 200-250mm from the seat back (2" window?). Am I to understand that if that dimension cannot be met due to cage design/seat positioning that a back brace of some sort must be used with the FIA seat? Or is that only for the homologation test procedure?

-Ryan

[Chip42]

Am I to understand that if that dimension cannot be met due to cage design/seat positioning that a back brace of some sort must be used with the FIA seat? Or is that only for the homologation test procedure?

Ryan, you're reading the instalation procedure for the homologation sled test, not into the car. My guess is that they aim to minimize but not remove the effects of the belts on the performance of the seat by using "average instalation" numbers.

The FIA standard for mounting an 8855-1999 seat is simply to mount it using those mounitng locations that were homologated (lower, lateral), and that those mounts be secure to the car. Some seats have both and only were homologated with one (typically lateral) others were tested with both, know your seat and make sure you're doing it right by referencing technical list 12 (link (http://argent.fia.com/web/fia-public.nsf/D19E318EE5F4920DC12577CA002C4759/$FILE/L12_Approved_seats.pdf)). contrary to popular belief, there is no FIA standard for seat mounts outside of those associated with the seat via 8862-2009, but all of the major seat manufacturers standard brackets are up to the task (many are made by the same factory). any catelog that lists brackets as "FIA approved" is not sufficeint evidence for homologation, but does mean that at some point an instalation using those mounts passed fia muster (or it's falacious information).

Your cage and the seats position have no bearing on each other outside of good design, but that's not in the GCR. Do check that you have clearance around the seat, that it is not "preloaded" by contact with or immediately next to a bar in the cage including the back (contact with the lower portion is more acceptable). make sure you have head room, pad any hard point you could get your head to. ensure that the belts are routed through the seat holes, not by them (the belt should not be deflected by the seat when tight). and use good hardware to mount the seat, mount to strong points, cage etensions, or using large, strong washers or drilled plate to spread the loads on the floor.

[Chip42]

some good guidance on seat mounting (not necessarily SCCA compatible but I saw nothing that jumped out at me, in general it is more strict) can be found here, article 16, pages 18-19 (http://argent.fia.com/web/fia-public.nsf/79839E53797F9746C125784D005E1787/$FILE/253%20(11-12)-080311.pdf). This is from European tourring car rules.

[Streetwise guy]

From the original FIA rules: http://argent.fia.com/web/fia-public.nsf/DA58BF07DFFA863FC1257690003E34B6/$FILE/253%20(10-11)-161209.pdf
Page 17 has the diagrams. Beware the braion cramps caused by attempting to read the FIA rule book.

ARTICLE 16 : SEATS, ANCHORAGE POINTS AND SUPPORTS

If the original seat attachments or supports are changed, the new
parts must either be approved for that application by the seat
manufacturer or must comply with the specifications mentioned
below :

1) Anchorage points for fixing the seat supports:

The seat supports must be fixed either:
- on the anchorage points for fixing seats used on the original car
- on the anchorage points for fixing seats homologated by the
manufacturer as an Option Variant (in which case the original
anchorage points may be removed)
- on anchorage points for fixing seats in conformity with Drawing
253-65B.
The seat supports must be fixed to the anchorage points for fixing
seats via at least 4 mounting points per seat, using bolts
measuring at least 8mm in diameter.
253-65B

INSTRUCTIONS DE MONTAGE

1- Percer des trous (Diamètre supérieur au périmètre des écrous)
dans le bas de caisse et la paroi du tunnel central.
2- Souder les écrous sur les contre plaques puis souder celles-ci
sur le bas de caisse et la paroi du tunnel central.
3- Souder les 2 inserts filetés dans la traverse puis souder les 2
platines aux extrémités de celle-ci.

FITTING INSTRUCTIONS

1- Drill holes (larger than nut outer diameter) in the bodyshell lower
rail and in central tunnel wall.
2- Weld the nuts on the counterplates, then weld these on the
bodyshell lower rail on the central tunnel wall.
3- Weld the 2 threaded inserts in the crossmember, then weld the
endplates at each end of the crossmember.

FIA Annexe J / Appendix J – Art.253

FIA Sport / Département Technique 18/19 CMSA / WMSC 11.12.2009
FIA Sport / Technical Department Publié le / Published on 16.12.2009

4- Fixer l’ensemble par les 4 vis M8 classe 8.8 qui se visseront sur
les écrous soudés.

2) Fixation des supports de sièges directement sur la
coque/châssis

Les fixations sur la coque/châssis doivent comporter au minimum
4 attaches par siège utilisant des boulons de 8 mm minimum de
diamètre avec contreplaques conformément au Dessin 253-65.
Les surfaces de contact minimales entre support, coque/châssis et
contreplaque sont de 40 cm2 pour chaque point de fixation.
4- Fix the assembly through 4 M8screws of 8.8 grade which will be
screwed in the welded nuts.

2) Fixing of the seat supports directly onto the
shell/chassis

Supports must be attached to the shell/chassis via at least
4 mounting points per seat using bolts with a minimum diameter of
8 mm and counterplates, according to the Drawing 253-65.
The minimum area of contact between support, shell/chassis and
counterplate is 40 cm2 for each mounting point.
253-65

3) Si des systèmes d'ouverture rapide sont utilisés, ils
doivent pouvoir résister à des forces horizontale et verticale de
18000 N, non appliquées simultanément.
Si des rails pour le réglage du siège sont utilisés, ils doivent être
ceux fournis à l'origine avec la voiture homologuée ou avec le
siège.

4) La fixation entre le siège et les supports doit être
composée de 4 attaches, 2 à l'avant, 2 sur la partie arrière du
siège, utilisant des boulons d'un diamètre minimum de 8 mm et
des renforts intégrés aux sièges.
Chaque attache doit pouvoir résister à une charge de 15000 N
quelle qu'en soit la direction.

5) L'épaisseur minimum des supports et des contreplaques
est de 3 mm pour l'acier et de 5 mm pour les matériaux en alliage
léger.
La dimension longitudinale minimale de chaque support est de
6 cm.

6) En cas d’utilisation d’un coussin entre le siège
homologué et l’occupant, ce coussin doit être d’une épaisseur
maximale de 50mm.
Tous les sièges des occupants doivent être homologués par la FIA
(normes 8855/1999 ou 8862/2009), et non modifiés.
La limite d'utilisation est de 5 ans à partir de la date de fabrication
mentionnée sur l'étiquette obligatoire.
Une extension supplémentaire de 2 ans peut être accordée par le
fabricant et doit être mentionnée par une étiquette supplémentaire.

ARTICLE 17 : SOUPAPES DE SURPRESSION

Les soupapes de surpression sont interdites sur les roues.

3) If quick release systems are used, they must capable of
withstanding vertical and horizontal forces of 18000 N, applied
non-simultaneously.
If rails for adjusting the seat are used, they must be those originally
supplied with the homologated car or with the seat.

4) The seat must be attached to the supports via
4 mounting points, 2 at the front and 2 at the rear of the seat, using
bolts with a minimum diameter of 8 mm and reinforcements
integrated into the seat.
Each mounting point must be capable of withstanding a force of
15000 N applied in any direction.
5) The minimum thickness of the supports and
counterplates is 3 mm for steel and 5 mm for light alloy materials.
The minimum longitudinal dimension of each support is 6 cm.

6) If there is a cushion between the homologated seat and
the occupant, the maximum thickness of this cushion is 50 mm.
All the occupants' seats must be homologated by the FIA
(8855/1999 or 8862/2009 standards), and not modified.
The limit for use is 5 years from the date of manufacture indicated
on the mandatory label.
An extension of 2 further years may be authorised by the
manufacturer and must be indicated by an additional label.

[Bremsen]

Thanks for the clarification Chip42/Streetwise.

[JoshS]

I admit, I haven't been following this seat brace mess.

Can someone boil it down for me? I have an FIA-approved Sparco Circuit that is less than 5 years old.

It is a side-mount seat, and I am using Sparco side mount brackets. The brackets are bolted to an adapter, which in turn is bolted into my car using the same mounting points that the stock seat uses. There is no slider.

Do I need a seat back brace now?

[seckerich]

If it slides, yes. If it is fixed no. CRB screwed that for us all.

[JoshS]

If it slides, yes. If it is fixed no. CRB screwed that for us all.

Thanks Steve. No sliders for me, the seat is fixed. I used to have Sparco sliders too but they had too much play, I couldn't stand them. For enduros we just find a seat position we can all live with.

[seckerich]

My old ITS car had a custom setup where the lower door bar on the left and a parallel bar along the tunnel had a sleeve inside and slots milled for 6 inches of travel. Four quick pins held it in position and it could easily be moved during enduro stops. Might go that route with the new car especially now that the inner tube can be welded to the floor/tunnel.

[Knestis]

Got my annual at Summit this past weekend and they did check for runners on my FIA seat, and one tech guy explained the new rule to another new guy. They didn't find any.

K

[Greg Amy]

I've already made two logbook entries of "fix before next race" to folks that didn't know. One had to bail on his first race because he couldn't fix it in time...

[dickita15]

While I am not a fan of the ban on sliders without a brace and think in time we may find a better compromise there was a reason for the rule change.
For those that have to deal with the change I will remind you there is a huge amount of freedom in how a seat back brace is designed.
I could build and install a legal brace in an hour with a hammer, vise and a piece of flat stock that would not be a spear. If it needed to be adjustable it might take an hour and a half.

[Chip42]

While I am not a fan of the ban on sliders without a brace and think in time we may find a better compromise there was a reason for the rule change.
For those that have to deal with the change I will remind you there is a huge amount of freedom in how a seat back brace is designed.
I could build and install a legal brace in an hour with a hammer, vise and a piece of flat stock that would not be a spear. If it needed to be adjustable it might take an hour and a half.

the chnage may be defensible in an otherwise logical rule.

fix the mounting rules, then see if the change is waranted. cat's out of the bag, but I personally see no logic behind it. carry on.

[Greg Amy]

I could build and install a legal brace in an hour with a hammer, vise and a piece of flat stock that would not be a spear.
Yes, but would it also have the designed-in flexibility to absorb energy that all FIA seats have? Or would it convert a very good seat into nothing more "safe" than something made out of lumber, sheet metal, and covered in leftovers from Aunt Tilly's sofa (which is also SCCA-legal as long as it is "securely mounted" and has a seat back brace)...?

[Knestis]

I'm going to make my brace out of the same material used in some RX7 rear suspension arm bushings.

K

EDIT - And what Greg said. Again. And again. It's so frustrating trying to take a meaningful, nuanced position that's actually grounded in SAFETY rather than meeting a rule. The Club spends so much time on the latter that they lose sight of the real point.

[seckerich]

While I am not a fan of the ban on sliders without a brace and think in time we may find a better compromise there was a reason for the rule change.
For those that have to deal with the change I will remind you there is a huge amount of freedom in how a seat back brace is designed.
I could build and install a legal brace in an hour with a hammer, vise and a piece of flat stock that would not be a spear. If it needed to be adjustable it might take an hour and a half.



And all because one person was too stupid to mount their seat securely and it came loose. As said before, stupid fix that is not grounded in reality. When you make a rule that you then suggest we "work around" that is less safe than the original rule we have all raced with for years you have failed at your job. Also reminds me of the same advice for motor mounts to use a chain.

[Chip42]

Also reminds me of the same advice for motor mounts to use a chain.

but that wont end up killing or paralyzing someone.

[dhardison]

So I have a Momo Start composite seat that is quite possibly past the 5-year mark (need to dbl-chk). If/when I install a 'spear', do I need to bolt it to the seat?

I know the GCR states that the brace must be "firmly attached", so I'm pretty sure the answer is yes, but "firmly attached" could be done with Gorilla glue, duct tape, etc. (I semi-kid). However I've read where Momo explicitly states NOT to drill holes in their seats, expired or not.........

Dan

[Chip42]

So I have a Momo Start composite seat that is quite possibly past the 5-year mark (need to dbl-chk). If/when I install a 'spear', do I need to bolt it to the seat?

I know the GCR states that the brace must be "firmly attached", so I'm pretty sure the answer is yes, but "firmly attached" could be done with Gorilla glue, duct tape, etc. (I semi-kid). However I've read where Momo explicitly states NOT to drill holes in their seats, expired or not.........

Dan

a new one is cheap. not as cheap as a brace, maybe, but much cheaper than whatever will happen to you if you drill holes in the shell.
http://ltbautosports.com/most20rasebl.html

[dickita15]

So I have a Momo Start composite seat that is quite possibly past the 5-year mark (need to dbl-chk). If/when I install a 'spear', do I need to bolt it to the seat?

I know the GCR states that the brace must be "firmly attached", so I'm pretty sure the answer is yes, but "firmly attached" could be done with Gorilla glue, duct tape, etc. (I semi-kid). However I've read where Momo explicitly states NOT to drill holes in their seats, expired or not.........

Dan

i would never drill holes in a composite seat. if you need a slider i would be thinking adhesive for the back brace but that is just me.

[Knestis]

The importance of what Dick is saying has been lost among the other issues. Read it again, everyone.

K

[Chip42]

i would never drill holes in a composite seat. if you need a slider i would be thinking adhesive for the back brace but that is just me.

a LOT of people have no idea how important this is. Wording to this end, along with guidlines and $&*^!!*# mounting rules (seriously) should be IN GCR 9.3.4.1

[Greg Amy]

i would never drill holes in a composite seat. if you need a slider i would be thinking adhesive for the back brace but that is just me.
I agree: drill no holes in a composite seat. But then again, (almost?) all FIA-approved seats are composite, so the SCCA is not only encouraging, but in some cases mandating, such modifications to composite seats.

RaceTech provides inserts for their seats that are 'glassed in, because SCCA Pro mandates seat back braces.

http://www.racetechseatsna.com/products.php?name=Seats/RTINSERTKIT.php

[dickita15]

There is nothing in the wording “firmly attached” that requires drilling holes.
I am just saying a length of flat stock, some double stick tape and a couple of muffler clamps to attach to the cage and I would sleep well.

[Chip42]

dick,

I think the people still following this all have the following in common:

*We believe in safety, not rules for their own sake with no demonstrable, positive effect on safety

*We understand the structural characteristics of fiber composites and the other designs common in racing seats, FIA and otherwise

*We understand ways to mitigate the problems of interaction between the particular seat and the back brace rule.

BUT there are a ton of racers who simply don't know this stuff. and the rules say they need to have a back brace on their FIA seat, say a momo start as came up earleir (GFRP). They see an add in sportscar for a back brace from IO Port and buy it, drill 2 holes, add some bolts, and go to the track. What they have done is unsafe, as we all know. but it is legal, meets a REQUIREMENT, and there is NOTHING in the rule to disuade them from this solution, nor guidance toward a safe construction, therefore there is nothing the tech can do other than recomend an alternative, but he's not able to rule it as illegal unless you give him a good rule.

had they a Sparco Sprint 5 or similar, they'd be bolting through nylon webbing. or maybe they'd realize that the brace and the seat aren't compatible, and get frustrated, miss their weekend, who knows. maybe they wind up in a economy kirky or a blow-molded Jaz. is that what we're trying to get them into? really?

meanwhile, those with and without sliders can continue to pop rivet their seat to rusted sheat metal using 3/8 washers because the existing rules are inadequate in that regard. yes, this is a stretch, but no, it is not illegal as written.

[dickita15]

Chip, I fully understand your frustration. I hope you remember I said I do not like the rule and was hopeful for a better solution. That a way can be found to allow a slider that is high enough quality to work.
The problem that spurred this rule is real. When someone buys a $1500 seat and then bolts it on top of a factory slider it causes a problem. When you can reach in and grab the top of a seat and it moves so much that it hits the cage it is a problem. So someone wrote a rule to address it.
Chip, I understand your frustration with rules that allow people to do poor mountings but I really do not want to go down the road where the rules are so narrowly written that you have no flexibility to install what is best for my own car.

[Russ Myers]

Don't keep the back brace straight. from an old book by Benny Parsons, put two bends in the back brace, z'ing the "spear". This allows it to remain rigid when holding your seat, and allows some give when chrashing.

Russ

[joeg]

Most composite seats I know of actually have holes drilled in them--in the side where the manufacturer installs nutserts for the side mounts.

I would not hesitate to drill and use nutserts for the back brace--if that defines "firm attachment". The problem is the brace.

[Chip42]

Most composite seats I know of actually have holes drilled in them--in the side where the manufacturer installs nutserts for the side mounts.

I would not hesitate to drill and use nutserts for the back brace--if that defines "firm attachment". The problem is the brace.

This is not true. FIA seat "nutserts" are embedded plates within the construction, the standard specifies they have a minimum area of 200mm^2, with the threaded hole centered within an enclosed circle of 40mm diameter (i.e. 20mm from the hole center to any edge of the plate). a nutsert will spin in a drilled hole in fiberglass with very little torque, and the hole interupts the fiber and introduces stresses to the resin, causing a reduction in overal strength and a yield point, as well as the liklihood of cracks propogatiing throughout the shell under vibration, so the seat is even more weakened just by using it, and before it is called upon to contain you in a wreck.

good explanation of how this works in Colin Chapman, Lotus Engineering by Hugh Haskell

the problem is both the stuctural integrity being compromised by those who are attempting to conform to a rule and don't understand the materials (thank you for proving my point) AND the danger posed by the "spear" should such a design (the common, off the shelf, advertised "easy button") be used.

[Chip42]

Chip, I fully understand your frustration. I hope you remember I said I do not like the rule and was hopeful for a better solution. That a way can be found to allow a slider that is high enough quality to work.
The problem that spurred this rule is real. When someone buys a $1500 seat and then bolts it on top of a factory slider it causes a problem. When you can reach in and grab the top of a seat and it moves so much that it hits the cage it is a problem. So someone wrote a rule to address it.
Chip, I understand your frustration with rules that allow people to do poor mountings but I really do not want to go down the road where the rules are so narrowly written that you have no flexibility to install what is best for my own car.

Dick, I'm not arguing with your position. but what I've been saying to you, this forum, the CRB in letters, etc... is that the failure(s)we've seen are the result of poor mounting rules. specify harware grades, minimum area of a washer for use when bolting to sheetmetal, forbid the use of factory sliders (THAT was a good rule), and make a statement about seat flex vs drivers head or the seat hitting cage elements (don't let it, pad with something like SFI 45.1/2 at minimum). how is that narrow? How does that change your ability to determine the appropriate seat installation for your car? The rule change that you suggest "addresses" the problem does, in fact, nothing to affect a change to it, it simply adds more stuff without guidlines or minima.

I agree that a back brace CAN be made to be safe, but I'm stating that it is NOT needed and ADDS confusion, complexity, and the chance for seat failure and driver injury, while addressing the ACTUAL problem (no mimimum guidlines for mounting) would have been a better FIRST action. Further, the fact that the rule does not make recomendations to help avoid unsafe instalations makes it worse than doing nothing. the other fact is that there is no one brace design that fits all seats and that can be proven safe without sled testing.

Will someone PLEASE explain to me how a back brace (without any spcifications other than "attached") is going to keep a poorly mounted seat from being dangerous? Especially when someone who mounts their seat poorly is apt to design and install their back brace with equal attention to detail?

CRB/BOD fail.

[Chip42]

fwiw, this is the lette rI sent to the CRB in AUGUST 2010.


Proposed rule, August 2010 Fastrack:

In 9.3.41, first paragraph, replace “Seat supports shall be of the type listed on FIA technical list No.12 (lateral, bottom,
etc).” with “Seat supports shall be of the type listed on FIA technical list No. 12 or No. 40 (lateral, lower, floor, back, etc) .In accordance with the FIA standards, the seat supports (brackets) must be those used when the seat was tested for homologation. Unless supporting evidence is provided by the manufacturer of a series produced car that shows FIA safety cage testing for homologation included an adjustable seat mount, seats and their supports must be attached to a fixed mounting structure.”

I recommend changing the language above to reflect that seats conforming to FIA standard 8855-1999, as listed in technical listing No. 12, are homologated with only the ”type” of bracket intended (8855-1999, 1.2) and NOT a specific seat mount part number. Technical list No. 40 specifies part numbers for the mount(s) used as they are homologated with the seat. Per 8862-2009, section 4.8 Seat-Brackets: “The seat brackets shall be considered part of the seat and shall share the seat homologation number.” This is a distinction that I think should be noted in the GCR as it has been misunderstood by many. It should be noted that the mounting of an 8855-1999 seat is subject to some level of official approval of fitness – I suggest this be by the scrutineer performing the annual inspection. It is odd to me that both the current and proposed rules are so devoid of specifics concerning the seat mounting. As a set of minimum criteria is needed in order to make a consistent determination in this regard, I propose a minimum of 3mm thick steel or 5mm thick aluminum should be used for mount brackets that are not identifiable as being from the manufacturer of the seat (be they generic, custom, or unmarked). These material dimensions are based on a sampling of the available offerings from several FIA-approved seat manufacturers. Seat mounts should be attached to the structure of the vehicle in such a way as to prevent movement in a collision; I recommend that it be in accordance with the driver’s restraint rules in 9.3.19.F. I also suggest the addition of ISO grade 8.8 as an alternate minimum fastener due to the common practice of using metric threads in FIA seat mounting bosses.

I believe that any rule requiring the addition of a back brace to a safely mounted seat is not well founded, even if well intended. FIA seats are typically NOT built to accommodate the installation of a back brace, and leaving the design of such a device to the competitor could result in required mounting that compromises the integrity of the seat back structure and could potentially cause serious, unintended harm to the driver. I have spoken to resellers and factory representatives from Cobra, Momo, Sparco, and OMP who all state that the addition of a seat-back brace to an FIA seat, particularly a composite shell seat, is dangerous and not recommended. Many of them offered stories of seats with back braces bolted to them that had cracked or been otherwise severely compromised in a wreck. Requiring replacement seat in order to properly accommodate a seat back brace could be crippling to a racer’s budget, particularly as many are still preparing to purchase required head and neck restraints, updated belts, etc…

Additionally, adjustable mounts for use in endurance cars can be a defacto requirement. Given the variety of cars that often cannot fit a back brace to allow both short and tall drivers (del sol, MR2, X1/9, etc…), and the potential for injury should the installed device compromise the seat back, there needs to be some language or provision for the use of adjustable mounts that conform to some acceptable standards that will allow the use of an 8855-1999 homologated seat without a back brace. These mounts need not (and in most cases, should not) be those supplied with the vehicle, but could be the type sold by the manufacturer of the seat or custom fabricated for the purpose and subject to some approval either at the scrutineering level or through a compliance review such as GCR 8.1.4. As it is very important to a large portion of the active community that there be a way to approve well designed mounting that permits quick repositioning of the seat, said rule must not rely solely on the seat or car manufacturer to offer an FIA approved adjustable mount, particularly as there is no applicable FIA standard for seat mounting brackets outside of 8862-2009 where they are co-homologated with the seat – meaning only certain exotic GT’s might meet the criteria as proposed.

As such, I recommend the following language in place of that proposed:

Seats homologated to FIA standard 8855-1999 are listed on FIA technical list No. 12 along with the type of support used in homologation, i.e. lateral or lower. In accordance with the FIA standards, the seat supports (brackets) must be the type used when the seat was tested for homologation. Where seat mounting brackets are not, or cannot be identified as being of the same manufacturer as the seat, a minimum material thickness of 3mm steel and 5mm aluminum alloy shall be used. Lower mount seats may be mounted directly to the floor of a production based vehicle, provided the attachment meets the minimum criteria outlined herein. Scrutineering shall be responsible for making a determination of the fitness of a seat mount and its installation.

Seats homologated to FIA 8862-2009 shall use the brackets homologated with the seat as listed in FIA technical list No. 40.

Seat brackets may be welded or bolted to the frame or roll structure of the car, bolted to the factory seat mounting bosses, or to steel floor boards of production based cars using 2” minimum diameter washers or equivalent. All bolts used should be SAE grade 5 or ISO 8.8 minimum, hardware without grade markings is unacceptable. Holes in the roll cage to facilitate bolting shall be bushed and welded completely.

Unless supporting evidence is provided by the manufacturer that shows FIA safety cage testing for homologation included an adjustable seat mount, seats and their supports must be attached to a fixed mounting structure. Exceptions may be approved on a case by case basis by a National or Senior Scrutineer or through the Compliance Review process (see 8.1.4). Mass produced items may be approved by the CRB and listed in the GCR.

The competitor is required to have a copy of the relevant FIA technical list and any additional homologation certificates or other certifying documentation on hand at all events.

[JIgou]

The brace that came in our new car:

http://www.ogracing.com/catalog/2-Car/36-Roll-Bars-and-Cages/item-1439-BREY-KRAUSE-COMPETITION-SEAT-BACK-BRACE

That's as far as I step into this discussion! :D

[the1jbh]

I am building a Miata for possibly ITA, Spec or SSM. I haven't chosen a seat yet because I have alot of the same concerns as you people. Any suggestions as to what, SAFE, comfortable seat to use? It will have to be on rails, because the car may be hot seated at HPDE's. I'm also not wealthy so, please spare me the big money butt pads. Thanks

[Chip42]

I am building a Miata for possibly ITA, Spec or SSM. I haven't chosen a seat yet because I have alot of the same concerns as you people. Any suggestions as to what, SAFE, comfortable seat to use? It will have to be on rails, because the car may be hot seated at HPDE's. I'm also not wealthy so, please spare me the big money butt pads. Thanks

no matter what you decide on, if it's on rails, it needs to have a back brace according to SCCA. first, I'd look for a set of double-locking rails a'la sparco in place of the factory bits. I prefer FIA seats, but you're into $2k+ stuff if you want one that has provisions for a back brace built in (RaceTech, the 4009W/HRV is the least expensive). so the second option is to find a seat you like and can afford, then fabricate a back brace following the logic in this and similar threads - don't drill into composites, distribute the load, and if at all possible, build in a fail point to allow it to deform with the seat flex.

good luck.

[Greg Amy]

I'd look for a set of double-locking rails a'la sparco in place of the factory bits.
Steve Linn just put a set up for sale:

http://www.roadraceautox.com/showthread.php?t=34408

[dickita15]

The other possibility is if the prime driver is the taller one you can use a booster pad for the shorter second Hpde driver. I use an aluminum seat in my car and I am the bigger guy so we have a pad that goes under and behind my team mate.

[Racerlinn]

Steve Linn just put a set up for sale:

http://www.roadraceautox.com/showthread.php?t=34408

Not anymore - sold to someone not club racing....

[Chip42]

The other possibility is if the prime driver is the taller one you can use a booster pad for the shorter second Hpde driver. I use an aluminum seat in my car and I am the bigger guy so we have a pad that goes under and behind my team mate.

I often wonder how wise this is. a good, non compressible insert would be fine, sure. but if the "pad" allows significant deformation, this opens a big can of worms, particularly in a hard rear-impact.

again - it's a "good idea" without enough caveats to make it clear to those who don't already know better.

[lateapex911]

I'll tell you, figuring out the seat issues, the HnR issues and so forth sure does give one pause....

[Chip42]

It'd be wiser if we all sat in front of a TV and played sims, but alas, we like the smell.

I can't figure out how the SCCA can on the one hand insist upon unilateraly breaking homologations by adding braces or ignoring expirations, leaving so much material safety to the competitor and stewards to judge for worthiness while not enforcing any standard besides (seats) - And on the other hand to be so attached to a single industry standard (HNR), with seeming 100% inflexibility. It's particularly odd given the inter-relationship between the two pieces of equipment: A failed seat leaves an SFI 38.1 HNR useless. (hybrid pro possibly being the exception, but you'd still be loose in the belts)

I know they feel that these decisions are in our best interests - but WTF? do they think it all through or is it a matter of different task forces reporting their findings and not workign together for a cohesive ruleset?

[lateapex911]

Exactly, Chip. Then add that, to my eye at least, the thing that's actually killing more drivers...and has the potential for far more collateral damage*....is individual health issues, and the physical standards we must attain are anything but well defined and strict.

* A driver that flies off track an strikes an object will suffer injuries as a result of an incident...but one who has a seizure of some sort while racing is the cause of an incident that can wind up injuring other drives, or worse, workers and spectators. If the club is so worried about the legal ramifications of allowing non SFI head and neck restraints, I'd think they'd be far more worried about the potential lawsuits that could result from an out of control car mowing down people in the pits after a race when a poor driver suffers a health incident.

So, on one hand I see we are being absolute in our insistance on adhering to the ridiculous SFI head and neck standard, stating that the club "Does not want to set standards", on another hand we're crafting illogical rules regarding seats while allowing, or even encouraging, seats that meet standards to be modified in ways that the manufacturers prohibit, and on a third hand we turn a blind eye to the 800 pound gorilla of actual recurring deaths.....

It's easy, for me at least, to get annoyed when one argument is used to defend for one subject but isn't even considered for another....but it's hard for me to aim my anger, because I know the club is made up of volunteers, and each does the best he can with what the club gives him. But you get the feeling that there's no central logic sorting going on at times.*

*And yes, I know I'm boiling things down, and some issues are complex, but when the end result makes little sense and the results are at odds with the goal, something needs to be fixed.

[Simon T.]

Still haven't made one, it's sort of my last thing to do before tech and the ARRC. I'm glad I read more though, my seat is fiberglass and drilling into it is a bad idea, right? So what are my options? The rules say it has to be firmly attached, any recommendations?

[joeg]

Urethane--3M Windoweld.

[barba]

You have to be very careful in attaching your seat and make sure that the placement of your seat is comfortable enough to the driver.