seat mounting rules

dickita15

dickita15

New member
Below is a draft of a letter I am going to send to the CRB. I believe a problem exists and would like some feed back as to whether I am on the right track and if anyone sees a problem with unintended consequences.

Dear CRB,
I am concerned about how to best mount a racing seat in class where there are limitations on the number of cage attachments points. It seems to make sense to attach the seat to the roll cage rather that to attach it to the sheet metal floor only. In my understanding of the current rules it is fairly simple to fabricate a frame or basket to support the seat and attach it to the cage at the rear of the seat. The basket can also be attached on the driver’s side to the door bars. The problem comes when you try to secure the right hand side of the “basket” to the tunnel it becomes an additional roll cage attachment point.
I would like to find a way to securely mount a seat to the chassis and the cage without violating the number of attachment points. I certainly do not want any rule change to inadvertently allow substantial chassis stiffening that would allow a competitive advantage.
If the CRB agrees that an issue exists and a stronger seat structure should be allowed maybe a rule such as below would be possible.
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 centerline 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 attachments.
 
I would argue the need. If the cage is fit tight to the unibody, you can plate the inner rocker panel and the tunnel. Run tubes between the rocker and tunnel, in front and behind the seat. Then build your seat mounts off of that. I have looked at lots of wrecked cars and have never seen any large movement in the drivers floor pan. Some small tears on a Shine customer car that hit NHMS oval wall and then got rearended. That was a massive hit and the seat did not move, even though there was a little tear in the floor underneath. Beran Peters also front end crashed his AS car at Mid O so hard it ripped the trans tunnel. I do not believe the seat moved on that one either. For safety sake I think we should be able to do anything we want including 360 welding to the unibody. It would also make cars live longer by stressing the unibody less. But I think the seat rule, if changed, will just open up a can off worms and add little true safety. Just my opinion.
Chris
 
zchris said:
I would argue the need. If the cage is fit tight to the unibody, you can plate the inner rocker panel and the tunnel. Run tubes between the rocker and tunnel, in front and behind the seat. Then build your seat mounts off of that. I have looked at lots of wrecked cars and have never seen any large movement in the drivers floor pan. Some small tears on a Shine customer car that hit NHMS oval wall and then got rearended. That was a massive hit and the seat did not move, even though there was a little tear in the floor underneath. Beran Peters also front end crashed his AS car at Mid O so hard it ripped the trans tunnel. I do not believe the seat moved on that one either. For safety sake I think we should be able to do anything we want including 360 welding to the unibody. It would also make cars live longer by stressing the unibody less. But I think the seat rule, if changed, will just open up a can off worms and add little true safety. Just my opinion.
Chris
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I's second that... I also think the cage rules are foolish. We have an endlessly growing number of safety rules, yet we don't want to stiffen the chassis by allowing the cage to touch it. That's nuts.
 
We always mounted the seats to the cage. If you got hit on the drivers side and the cage did move the seat moved with it. We ran two bars off the door bars and one down from the bar behind the seat but not back to the tunnel. Three mounting points were enough.
 
I have to agree with the naysayers. I think this is a solution to a non-existent problem. Mounting the seat off the rear hoop and side bars should be adequate. And even if you decided to attach the mount to the floor or tunnel, who would ever complain? I've never heard of such a protest, and anyone who would do so is revealing himself as a jackass. And I would hope that anyone reviewing such a protest would turn it down - it's a "strained or tortured interpretation" to call a seat mount a cage attaching point.

BTW, I once bought a car that had just such seat mount. Had won a bunch of races and never was protested. (I subsequently changed the mount, but only because I had to mount a bigger seat.)
 
Good luck. Not that its a bad idea but after hearing the CRB/ITAC say they could not see how to incorporate jack points w/o fears of it being abused I would say you're wasting your time.

Just my opinion - worth what you paid for it.
 
I am 100% in favor of this idea! For safety reasons (my perception no real data) I do think it would be safer and I am actually going to be changing my seat mount this year... As I have grown older I actually have started to think about safety... I have had bad thoughts about the way my car is currently set up. I am going to come up with some way some how to mount my seat and Belts exclusivly to the roll cage. The age and strength of my car is not nearly as strong as the cage and If my seat moves in compairison to the car I want my belts to move with it! Currently my rear belts are attached to the rear rollbar but my lap belt and sub belt are mounted to the floor along with the seat. Definatly not safe in my opinion. My fear the worst and envision a rollover and the rollcage "pops" through the floor. Then what... I literaly get squeezed into the seat or I flop around! So in conclusion this is a real thing that is on the top of my mind and I am 100% in favor of more strength and a more secure mounting for a drivers seat!

Stephen
 
Andy Bettencourt said:
Maybe it's not about protests - these cars should never make it through their first annual tech.
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Sez who?:rolleyes: Alright, I'll concede that a very literal reading of the cage rule could interpret the welding of a single 1" square tube to the floor as a ninth attachment point. But I would question the judgement of any tech inspector who would fail a car for such a seat mount. You are required to provide a secure mounting for your seat and a tube frame mounted to the cage and floor is about as secure as you can get.

I understand slippery slopes, so if some one tried to slip in a real extra attachment point(s), a tech inspector should say no. But to paraphrase Freud - sometimes a seat mount is just a seat mount.
 
TomL said:
Sez who?:rolleyes: Alright, I'll concede that a very literal reading of the cage rule could interpret the welding of a single 1" square tube to the floor as a ninth attachment point. But I would question the judgement of any tech inspector who would fail a car for such a seat mount. You are required to provide a secure mounting for your seat and a tube frame mounted to the cage and floor is about as secure as you can get.

I understand slippery slopes, so if some one tried to slip in a real extra attachment point(s), a tech inspector should say no. But to paraphrase Freud - sometimes a seat mount is just a seat mount.
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Which puts an unfair responsibility on a tech inspector to determine something he is not chartered or prepared to do. A 9th mount is a 9th mount is a 9th mount.
 
I am all in favor of making the cage/seat connection stronger. The data 'may' proove that is may not be necessaary but piece of mind about it goes a long way.


Andy Bettencourt said:
Which puts an unfair responsibility on a tech inspector to determine something he is not chartered or prepared to do. A 9th mount is a 9th mount is a 9th mount.
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Not too familar but...isn't the annual or first log book tech a saftey check? If so, I can show up with a cage that has 80 mounting points but as long as it has the correct main, size etc, it should pass tech? But then get caught out in a protest?
 
raffaelli said:
Not too familar but...isn't the annual or first log book tech a saftey check? If so, I can show up with a cage that has 80 mounting points but as long as it has the correct main, size etc, it should pass tech? But then get caught out in a protest?
Click to expand...

I think I am missing your point..

You are making additional points of connection.. if yo uinstall teh seat.. it will increase the rigidity to some degree of the chassis, much like a cage now already does. I have seen examples of seat mounts that sweep down from the lower door dars and main hoop and just rest on the floorpan of the chassis. which is 100% legal.
 
[

Not too familar but...isn't the annual or first log book tech a saftey check? If so, I can show up with a cage that has 80 mounting points but as long as it has the correct main, size etc, it should pass tech? But then get caught out in a protest?[/quote]

To answer your question--NO. The log book is issued to a car if it is compliant to all the class rules and safety is a part of that as well as obvious illegality. During an annual we do just check for safety items. Same goes for post race inspection which is limited to the 2 items on our prearranged list--no witch hunt. If we see something obvious count on it being on the list next race.:023: Normally an obvious item is brought to the owners attention to be fixed by the next race (except a safety item in case the tech police are reading)
 
zchris said:
I I have looked at lots of wrecked cars and have never seen any large movement in the drivers floor pan.
Click to expand...

The floor pan can and will move in a wreck. Below is a Spec 7 that I share a shop who took a hard hit a month ago. It is alledged he was purposefully taken out by another driver, but that's another story and can be found on another forum. Fortunately it was the passenger side but notice how much the floor pan moved up? If that would have been the drivers side his head would have been forced into the roof. Any HNR would be of no help when your head is ejected upwards.

I think the pictures below are a good argument for seat mounts that are integrated into the cage. I know I'll be doing a new seat mount on my car, but don't have to contend with IT rules anymore. FWIW, the cage in the car below held up fine.

It's also a good time to make sure your belts are mounted correctly. His sub belt was not, it was too far forward and ruined his new Sparco seat. Read the manufacturers installation instructions. Sub belt mounting for Schroth is here on page 16 - http://www.hmsmotorsport.com/docs/Competition_Instructions.pdf







 
seckerich said:
[

Not too familar but...isn't the annual or first log book tech a saftey check? If so, I can show up with a cage that has 80 mounting points but as long as it has the correct main, size etc, it should pass tech? But then get caught out in a protest?
Click to expand...

To answer your question--NO. The log book is issued to a car if it is compliant to all the class rules and safety is a part of that as well as obvious illegality. During an annual we do just check for safety items. Same goes for post race inspection which is limited to the 2 items on our prearranged list--no witch hunt. If we see something obvious count on it being on the list next race.:023: Normally an obvious item is brought to the owners attention to be fixed by the next race (except a safety item in case the tech police are reading)[/quote]

Ah, didn't realize. Got it. Thanks.
 
Seat and belt mounting should never ber attached directly to the tub of a prduction based car. It should always be attached to the cage structure.

The problem of the "third" mounting point discussed is it creates a place where the seat mount can bind an not allow the seat mount to move with the cage, especially the main hoop and the door bars. In the current SCCA cage rules you are allowed as many "touches" as you like so if you want you could put a foot on the seat mount at the right front corner but I'd only tack it to the mount and just let it rest on the floor pan.

Here's a couple of pics of how I do the seat mounts in production based road race and circle track cars. The pics don't include the belt mounting tabs, I don't add those on the seat mount tubes until I have the seat mounted and the driver in place to insure belt angle to avoid dumping.

DSCF1259.jpg


100_0996.jpg
 
those are nice setups..

for an effective seat bars, yo uwould have to build something similiar to the brackets above, then weld them to teh chassis. Jsut adding bars goign from teh lower door bars to the tunnel would do very little to nothing, if the assumption is that the floor pan is weak, the bars would be loaded in single shear.

I am not against the idea.. just if this does. please do it right.

but then again you can also argue seam welding for saftey, and cage bars to chassis welding.. for saftey..
 
You could also give that structure 'feet'. So long as they are not welded to the floor, you wouldn't have the extra attachment points and your seat would move with the cage as the safety contingent desires.
 
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