Mounting race seat

[jenson10]

A bit of a daft question, but I dont know the answer so I need to ask, what is the correct way to mount side mounting race seats in my saloon car, is a case of welding a couple of flat pieces of steel to the floor then bolting the mounts to them? thanks for the help in advance.

[Dom]

In all my Fiesta's so far I have just welded a length of modified box section to the floor to get the correct height in relation to the crossmember. then bolted or welded the seat mounts to those.
Depending on the car and seat models it may be possible to buy a subframe thats tailored to the application though - i belive OMP do these.

[jenson10]

Thankyou.

[greenamex2]

You need AT LEAST 'spreader' plates welded to the chassis floor if you are going to use the normal 'generic' mounts and bolt them in.

I didn't, a scrutineer pointed out my seat was a bit 'wobbly', we got home and found that was due to cracks in the floor pan!

[Alan Cherry]

I welded 2 box section tubes between the transmission tunnel and the sill - I used a sort of spreader plate at either end, and welded short sections of solid bar inside the box secion where the seat mounting (alloy side mounting plates) bolted on, so that I could bolt directly into the box section with no chance of crushing the tubes when I bolted up. - I've seen this solution quite a lot on Rally cars, and they get a much harder life than my race car ( except when I'm having a bad day ) I also made a mounting directly from the box section for the bottom mounting of the 6 point harness. _ don't know if that helps.
A quick question for the more learned out there - Are any of the sliding runners available FIA approved ? Reason is, I do a couple of rounds of the RCN each year ( Spa and the Nurburgring ) and the driver that I share with is quite a bit shorter than me - at present, I've made up a polystyrene/foam rubber block, covered with black tank tape that spaces him forward in the seat, but a sliding solution would be better if allowed - It's got to get past Spa/German scrutineers

Thanks
Alan

[Dom]

Originally Posted by Alan Cherry

A quick question for the more learned out there - Are any of the sliding runners available FIA approved ?

Demon Tweeks sent me a pair of sliding seat mounts a few years ago instead of normal side mounts - i'm 99% sure they were FIA approved (well at least they had an FIA logo on the sticker).

They're now gathering dust in my garage as I didn't think they would be substantial enough to cope with a serious accident.

[terence]

They have to be dual-lock to be approved,IE,both adjuster rails have to lock at the same time.Coming from DT,I would have thought they were this type.

[Alan Cherry]

Originally Posted by Dom

Demon Tweeks sent me a pair of sliding seat mounts a few years ago instead of normal side mounts - i'm 99% sure they were FIA approved (well at least they had an FIA logo on the sticker).

They're now gathering dust in my garage as I didn't think they would be substantial enough to cope with a serious accident.

Terence Bower wrote:
They have to be dual-lock to be approved,IE,both adjuster rails have to lock at the same time.Coming from DT,I would have thought they were this type.

Any chance you could check on the mounts that You've bought ? The OMP web site states that their seat sliders are not FIA approved, Sparco, Cobra and Corbeau web sites are all pretty vague on the subject, and looking at the FIA web site, there is loads on approved seats, but I can't find anything on approved mounts/runners.

Thanks
Alan

p.s going back to the original thread, I see that OMP now do a seat mounting Kit that mounts between the transmission tunnel and the side sill. Like the rally boys efforts - 2 lengths of cds tubing, 4 mounting brackets, trapped nuts to bolt the subframes into . about £38.00 - at that price I'd be tempted just to buy them - don't mess about making anything else !

[Southern Man]

Build your mounts either between the tunnel and the door sill or tunnel and roll cage. Mount your seatbelts crutch and lap straps off the cage or the seat mount supports and the shoulder straps off the rear of the cage. Don't mount off the floor as in a shunt the floor panel distorts and then your seatbelts come loose. Build yourself a survival cell of seat, cage and belts and let the car tear it's self to pieces around you. Hopefully you never need to test it to it's full potential, however, if you have to you will then forget about costs and effort and appreciate it's design and strength

[drjim]

Interesting point there.

I have had to mount my seat onto the floor so I have sufficient clearance between the roll cage and my helmet. There just isn't room to do what you suggest.

I keep thinking that if I go over a big kerb those bolts will be hitting the rumble strip. Might have to weld some box sections on to protect them.

[Southern Man]

Originally Posted by drjim

Interesting point there.

I have had to mount my seat onto the floor so I have sufficient clearance between the roll cage and my helmet. There just isn't room to do what you suggest.

I keep thinking that if I go over a big kerb those bolts will be hitting the rumble strip. Might have to weld some box sections on to protect them.

The floor panel is only there to keep the water and dust out of the car, it has no strength. I would suggest that in your case that you make up mounting frames that follow the contour of the floor but mount them as suggested previously. Try pushing down on the floor panel, or grab the back of the seat up by the head rest and apply some back and forwards force and observe the movement, then imaginge your body weight plus 3 to 4 G's and that is without distortion of the body by the crushing and crumple effect that occurs on impact.

Next remember that where you heat when you weld that you anneal the area around the weld (cars are made of high tensile steel these days) and that all the flexing will take place thought the annealed or soft area of the shell which is why it cracks around these flex or mount points. Radius the corners of all mounting plates and stitch weld rather than fully weld around the mount plates to reduce this effect and to spread the load across a greater area.

[Eddy V]

Usually bottom mounts are not homologated, unlike the side mounts. Why, I don't know, but probably because the many possibilities in floorpans. You can build your own without a problem, just follow the FIA guide.

Either paste this: http://argent.fia.com/web/fia-public.nsf/5CD029867CE2CF1AC12574FF00516990/$FILE/253%20(2009)-15112008.pdf

or http://www.fia.com/sport/Regulations/sportcoderegs.html, click on App. J 2009, open article 253 and scroll down to page 17, sub article 16.


Happy New Year!

[Dom]

Originally Posted by Alan Cherry

Any chance you could check on the mounts that You've bought ? The OMP web site states that their seat sliders are not FIA approved, Sparco, Cobra and Corbeau web sites are all pretty vague on the subject, and looking at the FIA web site, there is loads on approved seats, but I can't find anything on approved mounts/runners.

Have had a quick check and they are Sparco runners that conform to FIA Appendix J.

Hope this helps.

[Alan Cherry]

Originally Posted by Dom

Have had a quick check and they are Sparco runners that conform to FIA Appendix J.

Hope this helps.

Thanks - I'll get onto Sparco. Are they for base mounted seats only, or could I bold my side mounts to them - would be better if I could, seat is lifed for 5 years, and is only 1 year old.

Thanks
Alan

Edit: Cr*p spelling

[Alan Cherry]

Are they these ones ?

Can they be adjusted quickly? or do you have to remove 4 bolts, move, then replace and retighten 4 bolts ? - not exactly ideal for swapping drivers quickly !
any information much appreciated

Thanks
Alan

[Dom]

Originally Posted by Alan Cherry

Are they these ones ?

Can they be adjusted quickly? or do you have to remove 4 bolts, move, then replace and retighten 4 bolts ? - not exactly ideal for swapping drivers quickly !
any information much appreciated

Thanks
Alan

No they're basically flat runners and would be quite at home in a production car and are even probably adjustable on the move!. I'll see if i can get more info/pics over the weekend.

[Dom]

Alan, i've posted a couple of pics at http://fp.ryanhome.plus.com/drmotorsport/gallery.htm which might give a better idea. With the adjuster bar in place the mounting hole centres are 34cm apart.

Dom

[Alan Cherry]

Originally Posted by Dom

Alan, i've posted a couple of pics at http://fp.ryanhome.plus.com/drmotorsport/gallery.htm which might give a better idea. With the adjuster bar in place the mounting hole centres are 34cm apart.

Dom

Dom,
Thanks - I'll try and track a pair down - possibly at the racing Car show!


Alan

[Eddy V]

How many you want Alan?
Remember that they are not FIA and not always accepted in some championships.
But hardly anyone pays attention to them.

[Alan Cherry]

Originally Posted by Eddy V

How many you want Alan?
Remember that they are not FIA and not always accepted in some championships.
But hardly anyone pays attention to them.

Eddy,
If you look at Dom's photos, the Sparco Sticker has got the FIA label on it ?????
The only thing I thought I wasn't sure about, is that if you read the FIA regs chapter and verse, I believe they say something like ' original manufacturers runners ( Rover ones - had a look at some originals, and wouldn't touch them with a barge pole ) or FIA approved from the same manufacturer as the seat. Unfortunately, the FIA seat is an OMP, and only being 1 year old, I don't really want to replace it yet! Was going to use the seat in the RCN, as I share the drives with Matt Smith who is a good bit shorter than me ! Unfortunately, the cheif scrutineer ( who is a very nice chap) doesn't speak english, und mein Deutsch ist scheiss !
I'm now totally confused !

[Eddy V]

Mmm, might have overlooked that FIA thing for sliding systems. I'm old, what do you expect?
I'll have a look at the onces (OMP) we have next week when I'm back in the office. But you can use all Sparco items for OMP or Sabelt things (and the other way round), as they all have the same width, the same holes for the bolts, angle, ...