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Author Topic: Seat Mounting Hardware
mghenwood
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Region: Northeast
Car #: 58
Year : 1990
Posts: 61
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I am going to be mounting my new racing seat with custom brackets from Windsor Customs. What size and spec hardware do I need to meet the regs? I will be mounting to the stock seat mounts in the front and through the floor in the rear. Please include washer sizes or lock washers needed. Thanks.

Vick Verified Driver
Do they sell spec training wheels?

Region: NYR
Car #: 12
Year : 1991
Posts: 620
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When I had stock front humps, I used the actual screws that held the stock seat mount in place.

In the rear, I used grade 8 bolts (I figured why not). I forget the size, but I made sure the top part was not threaded.

Underneath the car I actually cut some 1/4" steel and made large washers out of them...I figured bigger surface area to spread any load and stress. I used nylocks and made sure I had a couple of threads showing once everything was secure. Some people prefer using lock washers compared to nylocks.

Also, in the rear some people weld an extra piece of metal where the mounts will penetrate the floor to reinforce things.

hope this helps.

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http://www.volko.com

Kent Carter Verified Driver Made Donation to Website
Future Never Has Been

Region: Houston
Car #: 91
Year : 1991
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Just keep in mind that the floor is very weak and will not support the mass of your body leveraged by the seat in case of a big hit. If you have an FIA-style seat this is compounded by the lack of a back brace.

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Do I turn my 99 Hard S into a killerfast SM or seek a donor?

mghenwood
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Region: Northeast
Car #: 58
Year : 1990
Posts: 61
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Yes I have a Sparco ProADV seat, so no back brace. I have welded 1/8" steel plates to the floor where I will drill for the rear mounts, and I am going to use 1/8" or 1/4" steel on the under side of the floor to spread the load as well.

Zauskycop Verified Driver
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Region: Chicago
Car #: 45
Year : 1991
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Hmmm...

I just used Windsor mounts also on my Pro 2000 seat. As everyone said, I used the stock hardware for the front, and I used Grade 8, 7/16" bolts in the rear. I just used a VERY large diameter grade 8 washer in the rear(the size you get with eyebolts for mounting belts) however. And I used Nyloc bolts for all hardware, no lockwashers

...Perhaps I should think about just making a plate for the washer? What do you all think...(I don't weld so for the time being, that won't happen) would a 2x2 1/8" plate do the trick for a backer?

Tracy Ramsey

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Tracy Ramsey
Team Blenderblaster

wheel Verified Driver Made Donation to Website
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Car #: 20
Year : 92
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Although the FIA seats are not required to have a back brace, it makes sense to have one, especially in a car where the seat is just mounted to the floor.
There are discussions about making the back brace mandatory, for all seats.

dsrgr Verified Driver Made Donation to Website
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Region: Las Vegas
Car #: 2
Year : 92
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I'm planning on buying the Ultra Shield 2010 Lightweight Road Race Halo. I couldn't find on their site that it meets FIA 8855-1999 so I assume I need a back brace.

Anyone else used this seat? Comments??

What back brace are folks using?

Keith in WA Verified Driver Made Donation to Website
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Year : 95
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1/8 x 2Ē sounds a bit small based strictly on my gut feel indicator however thatís what about what my USRP came with to mount the seat. For my ballast, I took a piece of 3/16 x 3 steel and cut two squares. My seat is on custom rails mounted to the stock hard points but if I were to mount it to the floor Iíd take that same piece of 3/16 steel and make one long piece that spanned 2 mounting holes but with one long piece 1/8Ē would probably be fine.

Remember with nylocks, after you remove and reinstall them a couple few times the nylon locking part doesnít work as well anymore.

--------------------
Keith Novak
(Will work for tires)

dtfastbear Verified Driver Made Donation to Website
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Region: SFR / NorCal
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This discussion comes up from time to time. Does anyone have any testing data for the safety and performance of FIA approved seats using a back brace? All FIA tests are conducted withOUT a back brace, so I'm wondering where the evidence is that they are safer (or safe at all, since they're designed to flex to absorb load) with a back brace.

I'm not trying to stir the pot, I'm actually curious. NASA requires a back brace once an FIA seat is out of certification (5 years), and I'd like to KNOW that this is a safe configuration. For safety items, I only trust testing, not just common sense, because testing often demonstrates that things don't behave in crash situations exactly the way you might expect them to.

Cheers,

Dean

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NASA Nor Cal SM series Director
www.molaps.com

Winner - Ford Racing Mustang Challenge Driver Shootout

Evil Genius Racing / Race Engineering / Stewart Development

Keith in WA Verified Driver Made Donation to Website
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quote:
Originally posted by dtfastbear:
For safety items, I only trust testing, not just common sense, because testing often demonstrates that things don't behave in crash situations exactly the way you might expect them to.

Very very true. Somtimes reinforcing one spot creates a worse weak spot somewhere else or drives much higher loads into other parts of your body...not always the ones you'd think. It would be hard to test uniformly though. Seats are constructed differently so where the holes and back brace are would make a huge difference seat to seat.

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Keith Novak
(Will work for tires)

Zauskycop Verified Driver
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Region: Chicago
Car #: 45
Year : 1991
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Has anyone actually ever seen the seat pull through the floorboard,and if so, what kind of backing was there??

Tracy Ramsey
Team Blenderblaster

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Tracy Ramsey
Team Blenderblaster

Blix Verified Driver
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Year : 1990
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You should use a MINIMUM of grade 8 hardware. Grade 5 or ungraded hardware is unacceptable, and that's ALL hardware, nuts, bolts, washers, lock washers, etc.

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Eric
http://www.hale-motorsports.com
For all your Mazda and Mustang needs

Keith in WA Verified Driver Made Donation to Website
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quote:
Originally posted by Zauskycop:
Has anyone actually ever seen the seat pull through the floorboard,and if so, what kind of backing was there??

Tracy Ramsey
Team Blenderblaster

While I havenít personally seen seat bolts pull out, Iíve seen a ton of cracks start at fastener holes in sheet metal. Fastener holes can be a big fatigue problem even in lightly loaded parts. Vibrations cause the cracks and the cracks can then grow quickly, dramatically weakening the surrounding metal.

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Keith Novak
(Will work for tires)

Zauskycop Verified Driver
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Car #: 45
Year : 1991
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Bringing this topic up again I do have one question:

I purchased two 4 x 6 " plates of 1/4 inch metal as "backers" for the underside of the floor. Painting them yellow as if one of those babies fell off, it needs to be seen. THAT said, I feel I should secure that with a second bolt. Would drilling a second hole in the floorboard to attach the plate weaken the floorboard too much if I did that? Is one bolt enough? Obviously, I will be using grade 8 bolts.

Tracy Ramsey
Team Blenderblaster

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Tracy Ramsey
Team Blenderblaster

Keith in WA Verified Driver Made Donation to Website
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I wouldn't worry about weakening the floor board like that and two bolts should be plenty.

--------------------
Keith Novak
(Will work for tires)

   

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