How do you mount your seat???

[RSTPerformance]

I was in some recent discussions about how to mount the drivers seat in the car...

The discussion debated attaching the seat (or I should say bottom mount) to the cage rather than the floor of the car. The thought was that the floor of the car is far more likely to get damaged/crushed and move vs. the cage. By move I mean distort so that the seat moves within the cockpit so that the driver could potentialy be crushed by the body and/or cage.

Not sure if I am explaining this right but I wanted others opinions...

Raymond

[Gary L]

If the cage is worth a damn, how are you going to distort the floor of the car without crushing the cage? And if you crush the cage badly enough to distort the floor, how you have the seat mounted is probably the least of your worries. Just my opinion, of course.

[JimLill]

How do the Pros do it? I'd look at a WC-GT car and see..........

[NutDriverRighty]

I don't recall the full details of the cage, etc., but I'd like to address the possibility of the floor deforming despite the cage and causing injury. I believe that it was two years ago at the July race at Road Atlanta that it occured. As I am told the story, Ony Anglade (excuse the spelling. I know it's wrong) spun at Turn 5, exited the surface driver's left, and "pancaked" the wall. The impact, though not seeming to be that bad to the T5 crew, was sufficient enough to distort the floor to the point that his head hit the B-pillar bar, causing a skull fracture. I'm sure that there are folks who know the story better than I and will fill in the details and errors that I missed.

Scott Franklin
ITA/IT7 and SPU
F&C

[Z3_GoCar]

Let's see... my seat is mounted to sliders that mount to the stock mounting points, or two studs and two bolts. The belts are also mounted on eye loops that are mounted (welded) to the floor with reinforcing pads. The only belt to mount to the cage is the shoulder harness which loops around the harness bar in the main hoop, although I could also use the rear stock mounting bolt and loop the shoulder harness over the harness bar.

James

[seckerich]

I mount all my seats from the cage. A pair of runners on each side of the seat hold the mounts and all belt mounts go to the tabs on the cage. There is a reason that classes faster than IT require it to be done. If that cage moves I want to be with it. :D

[Knestis]

One practical challenge is that cage mounting points are limited, and if the seat mounts are tied to the cage, it must be tied ONLY to the cage. Running a structure from the cage to the floor, tunnel, or inside of the rocker, then bolting a seat to it, is outside of what's allowed.

K

[dickita15]

One practical challenge is that cage mounting points are limited, and if the seat mounts are tied to the cage, it must be tied ONLY to the cage. Running a structure from the cage to the floor, tunnel, or inside of the rocker, then bolting a seat to it, is outside of what's allowed.

K
[/b]
Which is really something I wish the rules could address. The rear is easy to tie to the cage and it is not hard to tie into the door bars but I wish we could find a legal way to tie the seat support to the tunnel at the front of the seat without opening a can of worms.

[RSTPerformance]

Which is really something I wish the rules could address. The rear is easy to tie to the cage and it is not hard to tie into the door bars but I wish we could find a legal way to tie the seat support to the tunnel at the front of the seat without opening a can of worms.
[/b]


Yeah I thought about this issue as well...

How does the WC-GT cars do it??? Anyone have any pictures (legal/illigal IT mounts integrated into cage or even more interesting some pictures of the WC cars)?

Good point about the belts, mine do attach to the floor seperate from the seat mounting points, might be something I should change...

Thanks all for the input so far.


Raymond

[Knestis]

http://www.it2.evaluand.com/gti/images/seatmount2.jpg

We do this, then bolt sliders to the top and side mounts to the sliders.

K

[JamesB]

I need to remount mine, but I use a rigid mount since well its only me. But I also need to put about a 10 degree layback on the seat angle. With the hans I feel like I am head forward and dropping big money on a set with the hans bumpout just doesnt seem right to me.

[Greg Amy]

Kakashi Racing's c.2000 design (great minds do truly think alike). However, we use the square welded-in pads for the rear, and bolt vertically through.

http://www.kakashiracing.com/images/DCP_2455.jpg

[mtownneon]

I'm just a lurker here, learning all I can before I set out on my own IT project, but i can shed some light on cage mounted seats. I come from a stock car back ground and have done numerous cages in production based cars. You DO want to mount the seat and belts to the cage, not the floor. The cage and structure can do it's job perfectly and the floor pan can still fail. Think, if the seat is mounted to the floor, your weight in the seat is enough to bend that sheet metal in a heavy impact. If the seat moves independently of the cage and/or belt mounting points, neither will be able to help you survive.

The way I've always done seat mounts is to mount to the harness bar in the main hoop and off of the door bars. The right front corner of the seat mount assy 'floats', you don't want to attatch it to the floor or trans/ exhaust tunnel. For a full size guy like myself, I just add a small tube at that corner that just rests on the floor pan to add support for my weight. If the pan is thin, I'll tack a piece of 10 ga. under the stand on the pan.

You want to go wherever that cage goes, not where the car goes.

The best example of what I'm talking about happened to Micheal Waltrip some years back in a Busch car at Bristol. He hit the end of the outside wall coming off of turn two there after the entrance gate gave way. The car exploded into hundreds of parts, and the cage separtated from the frame as the body and frame disinegrated, all that was left was the cage's center section with the roof skin laying on top of it. Mikey, walked from that mess with minor injuries because the seat and belts stayed with the cage.

Dave

[JLawton]

You DO want to mount the seat and belts to the cage, not the floor. [/b]


The problem is what "should" be done and what the rules allow you to do, are two different things. The rules do not allow for an extra mounting point(s) coming off the cage. Whether there happens to be a seat also attached or directly to the floor, fire wall, etc......

[Greg Amy]

The rules do not allow for an extra mounting point(s) coming off the cage.[/b]
Yes, but what Dave describes above - if I am inferring correctly - is legal to the IT rules. Imagine a half-hoop coming off the main cage and looping around to a low-rocker-panel door bar, without being welded to the floor/chassis anywhere. Weld a vertical "stub" going from the right-front corner of that hoop down to the floor, but don't weld the bottom of that stub, rather let it "touch" there (remember, rollcage "touches" aren't mounting points).

Mount the seat to that half-hoop, and now you have a seat mounted to the cage but not the floor.

An intriguing idea, actually.

[Z3_GoCar]

Also, I don't know about anyone else's application, but rooms pretty tight for running extra tubes off of the door bar or main hoop. If I were to mount to the door bar I'd have to cut into the side structure of the uni-body. We don't run tube frame cars like the Cup cars. Think about this, my car was engineered to run the Autobaughn at unlimited speeds, how can a cage mounted seat be any better than the stock mount?

James

[Team SSR]

"how can a cage mounted seat be any better than the stock mount? "

The addition of a properly mounted cage is going to drastically change how the car crushes in a severe impact.

[DavidM]

If your seat mounts to some sort of cage structure then your belts should also mount to the cage somehow as well, right? Sounds like you almost have to fabricate an entire seat "holder" if you will that attaches to the cage. It not only has to hold the seat, but provide points to attach the belts. You'd have to have something going under the seat for the sub-belt. I'd love to see a picture of some sort of setup like this. The seat/belt mounting in my car has always not look the best to me.

David

[Sandro]

I was doing my seat mount about a month ago and also didnt know what to do because of what the rules say. I was thinking of the same thing as Greg and sent this exact picture to the CRB and got shut down. They said someone could say that its adding additional reinforcement to the car. :bash_1_:

http://i48.photobucket.com/albums/f231/Kanoa9321/SeatMount.jpg

[mtownneon]

[attachmentid=1003][attachmentid=1002]

Here's a couple of illustrations from CSC Racing's web site on their seat mount kit. It's a little more complicated than it needs to be but it gives everyone the basic idea.

I used MW's crash as an extreme example of the effects of having a properly mounted seat. Although a cup car is tube frame construction for sake of argument, a stock chassied pure stocker or a road racing IT car's basic cage and lay-out are the same.

The belts are attatched via tabs welded to the same "frame" that the seat is attatched to. The idea is to keep the seat, belts, and you all in place if the worst happens.

[JoshS]

Although intriguing, I think that's unnecessary in a unibody design (vs tube frame, where it makes a LOT of sense.)

[Chris Wire]

Although intriguing, I think that's unnecessary in a unibody design (vs tube frame, where it makes a LOT of sense.)
[/b]

I don't know if I'd characterize it as "unnecessary". It may be overkill, or simply ambitious. Unnecessary indicates to me that it serves no valid function, which I would disagree with.

That being said, I mounted mine to a couple of steel straps attached to the factory mounts directly on the floor. Sorry no pics at present.

[Knestis]

I was doing my seat mount about a month ago and also didnt know what to do because of what the rules say. I was thinking of the same thing as Greg and sent this exact picture to the CRB and got shut down. They said someone could say that its adding additional reinforcement to the car. :bash_1_:

http://i48.photobucket.com/albums/f231/Kanoa9321/SeatMount.jpg
[/b]

This is a great example of precisely why we need to not ask questions through that kind of process. It's not binding in any helpful way (if they'd vetted it, you'd still be screwed if a protest found against you), and the negative responses create arguements for doing silly things - like building a seat mount that isn't as strong as what you've drawn.

Protest my seat mount, someone. Go ahead. :blink:

K

[Z3_GoCar]

I'd say turn your tubes around, you've got that nice structural member that should run under the front of your seat and then the second just behind and below your rear cage tube. That should probably be the front and back of your seat mounts.

James

[Knestis]

...but you can't tie to the cage, then to the chassis. That's additional rollcage mounting points.

I'm not saying that is how it SHOULD be, just that it is.

K

[Z3_GoCar]

No Kirk,

I'm talking about the chassis element you can see in the upper left of your picture. Run your main tubes horizontally instead of virtically like you have in your picture. I use a similar structure where the stock seat tracks mount to in the front and the rear has some double wall floor elements with threaded inserts.

James

[Knestis]

Ah, sorry - I thought you were talking about that cage tube in the picture. Reading really IS fundamental, I guess. :)

K

[JimLill]

On a VW, I'd think about where VAG put the stock load-bearing connections to the unibody. Given those carry the body load via the seat and at last one end of the seat belt, those metal areas must be quite stout. Other adjacent areas may not have the same strength/rigidity.