• vizlvr
  • vizlvr
  • Ripened Lemon
  • Offline
  • From: San Mateo, CA
  • Registered: 2009-11-21
  • Posts: 128

Topic: i/o Port Seat Brace Question

We were planning to use the i/o Port Seat Brace but missed that it is supposed to be bolted to the seat back.  This is not going to be particularly feasible for us as it would require removing the seat upholstery which is not designed to be removed. Does anyone know if it HAS to be bolted to the seat?  The seat brace in general does not have to be physically attached to the seat, correct?

Thanks!

Import Alloy Racing
The Little Red Poorvette
  • From: Hayward, CA
  • Registered: 2010-03-23
  • Posts: 1,762

Re: i/o Port Seat Brace Question

What's the benefit of a seat brace that isn't bolted to the seat? it MIGHT only work in a straight ahead impact. But you can't be dependent on something that happens once in a million crashes. Most crashes are going to involve loads from many directions so it does need to be bolted.

Can't remove the seat cover? Why cause its a nice new seat? Just drill a couple holes and get over it. or look along the bottom and open those steel rings and undo the cover, then mount the brace and put a hole/slot in the cover where the brace goes through. If your really fancy, have someone with a sewing machine stitch a oval or a hole and cut out the center so it looks like it was supposed to be that way.

And put an aluminum plate on the front side so the bolts don't tear out.

Dudes Ex Machina: https://www.facebook.com/dudesexmachina

?Everyone who has ever built anywhere a 'new heaven' first found the power thereto in his own hell- Frederick Nietzsche
  • fifty
  • Paddock Rat
  • Offline
  • From: Little Rock, AR
  • Registered: 2010-03-14
  • Posts: 24

Re: i/o Port Seat Brace Question

mackwagon wrote:

What's the benefit of a seat brace that isn't bolted to the seat? it MIGHT only work in a straight ahead impact. But you can't be dependent on something that happens once in a million crashes. Most crashes are going to involve loads from many directions so it does need to be bolted.

.

The seat brace is to prevent the seat folding backwards in the event that the rear of the car collides with something (such as spinning backwards  at high speed into a tire wall) So, it only has to work in one direction, give or take.

We didn't bolt our brace to the seat, just snugged it up against the seat back, as did most other teams I looked at. We passed tech.

fifty's Website

4 Reply by vizlvr (edited by vizlvr 2010-08-01 07:13 PM)

  • vizlvr
  • vizlvr
  • Ripened Lemon
  • Offline
  • From: San Mateo, CA
  • Registered: 2009-11-21
  • Posts: 128

Re: i/o Port Seat Brace Question

mackwagon wrote:

What's the benefit of a seat brace that isn't bolted to the seat? it MIGHT only work in a straight ahead impact. But you can't be dependent on something that happens once in a million crashes. Most crashes are going to involve loads from many directions so it does need to be bolted.

Since having the harness bar within 6" of the seat  (which, obviously, does not involve bolting anything to the seat) qualified for adequate seat back bracing I didn't think this was that ridiculous a question.

mackwagon wrote:

Can't remove the seat cover? Why cause its a nice new seat? Just drill a couple holes and get over it. or look along the bottom and open those steel rings and undo the cover, then mount the brace and put a hole/slot in the cover where the brace goes through. If your really fancy, have someone with a sewing machine stitch a oval or a hole and cut out the center so it looks like it was supposed to be that way.

And put an aluminum plate on the front side so the bolts don't tear out.

No, because it's an ebay seat we've had in the garage for several years and the 'seat cover' does not look to me like it would be happy being removed and reinstalled and the structure of the seat itself doesn't seem likely to support this anyway (even with a front side plate).


fifty- Thanks for the reply.

Import Alloy Racing
The Little Red Poorvette
  • From: Wadsworth, OH
  • Registered: 2010-07-29
  • Posts: 115

Re: i/o Port Seat Brace Question

If the structure of the seat is questionable I would suggest not using it.  Your original questions is legitimate to me, but your reasoning for asking it seems questionable.  If the seat looks like it is gonna come apart I doubt it will pass tech itself regardless of the the brace.

  • vizlvr
  • vizlvr
  • Ripened Lemon
  • Offline
  • From: San Mateo, CA
  • Registered: 2009-11-21
  • Posts: 128

Re: i/o Port Seat Brace Question

It's not going to come apart, its just not an aluminum race shell.

Import Alloy Racing
The Little Red Poorvette
  • From: Hayward, CA
  • Registered: 2010-03-23
  • Posts: 1,762

Re: i/o Port Seat Brace Question

fifty wrote:
mackwagon wrote:

straight ahead impact

The seat brace is to prevent the seat folding backwards in the event that the rear of the car collides with something (such as spinning backwards  at high speed into a tire wall) So, it only has to work in one direction, give or take.

We didn't bolt our brace to the seat, just snugged it up against the seat back, as did most other teams I looked at. We passed tech.

Should have said "straight on impact". An unbolted seat back brace will only work correctly for a direct rear end or front end collision (when the car bounces back off the impact). But you still want it bolted so that the seat and you move less forward in a frontal impact.

And that only has to work in one direction, give or take, is exactly what I was trying to point out by saying there are many different directions of loading happening in an accident. You can't predict what "direction" the hit is coming from so you need to have it bolted. If you don't you might be supporting one shoulder and not the center due to a angled hit and then next thing you know your body is twisted 90 degrees in the impact and you have major back injuries.

Since it is an old seat, just drill it through and again put an AL plate on the front side. Use either Carriage bolts for low bolt head height, or use a countersunk Allen bolt.

Dudes Ex Machina: https://www.facebook.com/dudesexmachina

?Everyone who has ever built anywhere a 'new heaven' first found the power thereto in his own hell- Frederick Nietzsche
  • From: Houston - Katy
  • Registered: 2010-08-04
  • Posts: 361

Re: i/o Port Seat Brace Question

Is this seat brace a mandatory item or one that experienced teams go for to improve driver safety?  If the roll cage is modified to have a brace running across the rear of the seat, would this be sufficient?

Thanks

Is it because I is an E30 owner???
  • Mulry
  • Mulry
  • Ayatollah of Rock-n-Rollah
  • Offline
  • From: Dallas, TX
  • Registered: 2009-05-01
  • Posts: 4,607

Re: i/o Port Seat Brace Question

The rule is that the back of the seat must be no more than 6" from a rearward support at all times. This is to prevent the seat from tipping backward significantly in the event of a strong rear-ender.

If your cage is designed such that the seat is never more than 6" forward of the brace across the back of the seat, then you don't need an adjustable brace.  However, if you have sliders that permit the seat to travel such that the back can be more than 6" forward of that fixed brace, then you'll need an adjustable brace. We use that i/o port one but you could easily fabricate one that does the exact same thing for far less $$$. But if you get in a time crunch before the race, the i/o port one is just swell.

Pat Mulry, TARP Racing #67

Mandatory disclaimer: all opinions expressed are mine alone & not those of 24HOL, its mgmt, sponsors, etc.