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.
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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.
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.
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.
So I guess I need to drill through the seat to attach it.
Thanks for the posts!
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>
Most FIA seats cost a lot more than a non FIA seat.
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]
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.
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.
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?
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.
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
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.
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
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.
And many thanks to Chip for pointing this issue out to me. I totally missed it in all the jibber jabbah.
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.
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...
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.Quote:
Because this whole seat mounting issue is starting to be a real pain in the ass.
GA
There are FIA approved sliders available.
http://www.discoveryparts.com/cgi-bi...s_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.
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.
Those sliders are NOT FIA approved. Go to the Recaro web site http://www.recaro.com/en/product-are...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
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.
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
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.
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.
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.
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.
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.
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.
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.
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.
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
-----Original Message-----
From: Dave Gomberg [mailto:[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
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.
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