71 replies to this topic

[David S.]

I thought I read on here somewhere that stock sliders would fail tech? Either way, I sold my stock seats with the sliders attached and had the sparco ones left over from my previous car.

[RazerX]

I think i would have had my racing steering wheel in to test seating position. The mount, dish, diameter, etc change change your hand position and where you are comfortable. I understand it is on sliders but i like remove variables whenever i can.

[wheel]

If you use stock sliders the seat back has to be braced, as the stock sliders are not the sliders used with the FIA certification process. The same applies to any other sliders that were not part of the FIA certification.

wheel

[David S.]

I think i would have had my racing steering wheel in to test seating position. The mount, dish, diameter, etc change change your hand position and where you are comfortable. I understand it is on sliders but i like remove variables whenever i can.

This.

Being my first time ever building a race car, there is a lot of trial and error. I have put the cart before the horse more than once. I got my steering wheel installed yesterday and am not really happy with the seating position. The wheel sticks out pretty far and I can't move the seat back as far as I would like because it hits the rear down tube of the cage. At this point I am planning on ditching the sliders and mounting it solid. Maybe even putting it on the floor. It is amazing how much smaller these cars get when you start putting a cage, different seat, and removable steering wheels in them.

[Bench Racer]

David, the drivers area is about the most serious area there is for ongoing driver comfort. Before you go further with any part of your roll cage install your seat.......... If all you have is the main hoop installed (I don't see front tubes or side protection tubes.) you may be ahead of the game by taking the main hoop out (sometimes a step backwards is a gain) and starting over after all the driver features/comforts are in place. Now sounds like a good time to sit in a few different cars with finished roll cages.

How much interfearance is there with the main hoop for the seat not being able to be placed further rearward? If you don't care for the idea of removing the main hoop, could you move/tilt the seat a bit to the right so the seat can be further rearward.

When you plane the side protection tubes (NASCAR tubes) be sure to install them for maximum elbow flying room. Set in the seat and work your elbows far out and up and down through all potential places your elbows could be.

Have Fun
David

[David S.]

David, the drivers area is about the most serious area there is for ongoing driver comfort. Before you go further with any part of your roll cage install your seat.......... If all you have is the main hoop installed (I don't see front tubes or side protection tubes.) you may be ahead of the game by taking the main hoop out (sometimes a step backwards is a gain) and starting over after all the driver features/comforts are in place. Now sounds like a good time to sit in a few different cars with finished roll cages.

How much interfearance is there with the main hoop for the seat not being able to be placed further rearward? If you don't care for the idea of removing the main hoop, could you move/tilt the seat a bit to the right so the seat can be further rearward.

When you plane the side protection tubes (NASCAR tubes) be sure to install them for maximum elbow flying room. Set in the seat and work your elbows far out and up and down through all potential places your elbows could be.

Have Fun
David

Thanks for the tips. The main hoop/harness bar/ rear down tubes are all in but only tack welded. My dad wanted to pull them out of the car to do the final welding so it is coming out anyways. I am hoping that by getting rid of the slider (and therefore dropping the seat by ~.5") I will be able to move the seat back enough to make it comfortable. If not, the seat may end up on the floor as I think that would definitely give me enough room.

I'll make sure to check the elbow clearance when installing the side bars.

Thanks again.

[Danny Steyn]

David, the drivers area is about the most serious area there is for ongoing driver comfort. Before you go further with any part of your roll cage install your seat.......... If all you have is the main hoop installed (I don't see front tubes or side protection tubes.) you may be ahead of the game by taking the main hoop out (sometimes a step backwards is a gain) and starting over after all the driver features/comforts are in place. Now sounds like a good time to sit in a few different cars with finished roll cages.
David

Good advice!

[Alberto]

YOu can get different hubs to change the steering wheel position. I adjusted mine a few times using different hubs and steering wheel spacers. The steering wheel is easy to move.

On the other hand, the pedals and clearance between your head and the roll bar are difficult (and expensive) to adjust. When I was working with TC Design on building my cage around me and my seat, we positioned me in it, got the distance to pedals and then figured out amount of layback needed to clear bars and such. Then I played with steering wheel position on my own.

Need the wheel further away, get an NRG short hub. http://www.amazon.co...H/dp/B001G0CYHK

The wheel too far with the NRG short hub? Use a regular off-the-shelf Momo hub.

The wheel not close enough with the regular Momo hub? Use a spacer - 1/2", 1", 1.5", 2". http://www.advanced-...products_id=143

or try a dished steering wheel

Is the steering wheel now positioned too high? Want to drop it a little lower? Unbolt the steering column from the dash bar and find some longer bolts in the same pitch and thread and some spacers or washers.

I've been meaning to write a blog post about this topic but been too busy with work lately. PM me if you need to exchange some ideas.

[Ron Alan]

"Is the steering wheel now positioned too high? Want to drop it a little lower? Unbolt the steering column from the dash bar and find some longer bolts in the same pitch and thread and some spacers or washers"

This legal??

[Alberto]

"Is the steering wheel now positioned too high? Want to drop it a little lower? Unbolt the steering column from the dash bar and find some longer bolts in the same pitch and thread and some spacers or washers"

This legal??

It was according to the last discussion on the topic.

Full disclosure, I added about 1/2" of spacer to mine. Been like that for quite some time. That's why I'm so fast.

[David S.]

I took everyone's advice and redid a few things today. First up was the steering wheel adapter. The one that came with the kit I bought was a nice piece except it stuck out a little far for my liking. So I bought the NRG short hub mentioned a few posts up and installed it. For anyone who plans to do this: I had to have my dad weld the quick release shaft on the opposite side of where it is welded originally. That has to be done so that you can cut the excess tubing off of the back of the flange. The new hub is so short that the excess gets in the way and you can't bolt it down. Not a big deal, but I wanted to mention it so that nobody buys it and expects to bolt it right on.

 

Height difference between the two hubs:

 

 

New hub installed. You can see the new weld here. That tube stuck out the back of the plate too much for them to work together.

 

 

I also got the seat mounted in a much nicer way. I ditched the slider and mounted the seat directly to the Good-Win Racing base. I then spaced the front of the base up about .5" and love the way it feels. I also took a hammer to the trans tunnel so I could move the seat to the right some. The seat is much easier to install in the car, sits lower, and is now centered with the steering wheel. All little changes, but I am much happier with the car now then I was before. I didn't get pics because we got busy working on the cage. I will make sure to take some the next time I am there and put them in this thread.

[Adax]

All,

Seats that have been homologated to and mounted in accordance with FIA standard 8855-1999, or seats that have been certified to FIA. Standard.8862-2009 or higher need not have the seat back attached to the roll structure

1. Seats do not go out of date.
2. This means just what it says. If the seat was homologated and is mounted in according to the standards, it DOES NOT NEED the back attached to the roll cage. It can be, if you want it to be, but it is not required. If you have an FIA seat, but it was not mounted according to the standards, you need a back brace. So, if you have an FIA seat and it is mounted with brackets made out of Coors cans, it is not mounted according to the standards and requires a back brace.

 

 

So my reading of this is that for the seat to be truly compliant, it must be mounted with the same mount as it was tested with during certification. So, it is not technically legal to mount my Sparco seat using my OMP mount?

 

From FIA Standard 8855-1999

 

1.2
Each seat shall be homologated with its type
of supports: lateral supports, lower supports.
The tests described below shall be carried out
with the type of supports defined by the
manufacturer at the time of the homologation.
One and the same seat may be homologated
with different types of supports (lower, lateral).
In this case, two complete series of tests shall
be carried out.
The type of supports with which the seat was
homologated will be clearly indicated in the
test report and on the list of FIA-homologated
seats.