jgrant

I'm 5'8", 260lbs, and the OMP "Big Guy" seats fit perfectly... One of them's going in my car in 2 weeks.


http://www.ompracing.it/detail.html?productcode=HA/703


$0.02 (CDN)

DGaunt

This is a great thread for us well nourished guys. I?t could be even more useful if people who respond with comments on a given seat could share thier size and weight so we can concentrate on the comments from those of similar body sizes.

I am 5'11 and about 280 lb, and would like to find a sliding seat with lumbar support for bith track and street. Harness holes preferred.

I know someof you have stated your size, but if more did, the comments would be more usable.

A930Rocket

I'm 6' 4'' and 250lbs. When I was living in Charlotte, SC a few years ago, I went up to Butler Built and had them measure me and had a seat made. I've since then added the shoulder and head supports, but need to adjust them.

kary993

I am not sure from your picture how you actually drive very well with your arms locked out like that. Very tiring and somewhat dangerous in the final analysis. was this because of head room and the angle of your seat?

BTW, Like the Isaac in the picture!!

Premier Motorsp

More things to consider--

Fiberglas seats 'break in' quite a bit. I am 6'2'' 230-250 depending on how much GF is cooking. I fit in 'my' Recaro SPG pro racer just fine. When the seat is new, or broken in by a small person, the fit is really tight. People claim I have a small *** for someone of my height and weight. Everyone is different. I do know that I am swimming in a Pole Position.

If you are over 200 lbs and you get your car handling good and then race quite a bit, you are probably going to tear up the seat mounts. Keep a eye on these. The aluminum side brackets will break too, especially when you modify them to get the seat lower.

This is why I have an inherent distrust of aluminum seats. I just know that seat is going to get a huge crack in the first 10 minutes of a 90 minute race.

Chris Cervelli
Premier Motorsports

baldheadracing

Kirkeys must be installed with seat back braces. That's why they do not/will not pass FIA tests. FIA requires seats to be solely floor-mounted - mainly so they will work in four-door sedans that do not have a roll cage. Kirkeys are meant to connect to the roll cage in multiple places (preferably including the door bars).

There's an awfully big difference between a Subaru WRX (a typical FIA GroupN car) running in a rally in a forest (where you want flex), and a tube-frame Modified running in a concrete wall-lined oval (where the same amount of flex would be dangerous). In any case, history means the approaches are totally different.

Note FIA has different seat mounting requirements for different classes - for example, my Recaro Pole Position came with no headrest foam (of any safety consequence) as different FIA series have different headrest foam requirements. The higher-powered FIA series also have requirements for structures on the roll cage/door bars to contain the seat - so the two worlds are a lot more alike once you read all the regulations.

Kirkey is a Canadian firm, not a German one.

P.S. The Kirkey road race looks like about a 20 degree layback to me, and does have much less "butt cup" than other Kirkey's (like my old Speedway deluxe 20 degree layback), namely to allow for easier ingress/egress.

Geo

I have downloaded the FIA seat homologation papers and don't ever remember reading that. As I understand it, the manufacturere specifies exactly how the seat must be mounted for the tests and the homologation is only for this mounting configuration.

baldheadracing

You are correct. However:
- the manufacturer has only two choices for seat mounting - side mounts or bottom mounts. (General test condition 1.2 of 8855-1999) I realize the English translation of the regulation doesn't use these terms, but the French is specific.
- the attachment points to the test rig are all on the "ground" in the "standard position" (drawing 3).
- the distance between the test rig's "post" (i.e., where a seat back brace would be mounted) and the seat assembly must be a minimum of 150mm (Section 2). This alone makes the use of a seat-back brace impossible - even a manufacturer-supplied rear brace exists (which is true for the Kirkey Road Race),

Geo

This is very interesting indeed! Thank you so much for that info. So, this is basically saying one should have about 6" minimum clearance between a properly mounted FIA homologated seat at the main hoop cross bars.

RedlineMan

A930Rocket - Thanks for posting those pics. I don't think you intended to prove my point, but thanks nonetheless.

These pics illustrate perfectly what I was trying to say, not only about how the Kirkey seats "work," but about the parameters that make up a good installation. Because he is tall, A930 has headroom issues. However, to set the seat back where you have headroom, you lose reach. To improve reach, you lose headroom.

As Kary points out, this is not a great setup. I would not go so far as to say it was dangerous, but it is far from ideal. As he mentions, this does not offer the drivera lot of leverage on the wheel, which can become quite tiring over long periods. So too does this distance decrease the agility during evasive or emergency maneuvering.

This is not to say that it can be easily rectified either. This is a perfect opportunity for those who felt they had a good handle on seat positioning to try and come up with a solution for this "problem." I think in a very short time, you will agree that it is NOT an easy problem to solve. Welcome to my world!

In my 944, I created headroom by completely removing the rear seat mount "pads" on the floor, and also the cross beam where the front seat mounts were located. I fabricated angle iron cross braces right at floor level that the seat mounts sit in, and the seat bolts THROUGH these floor mounts with nuts under the floor pan. As low as you can go without cutting the floor!

Still... my reach was like A930's. If I tipped the seat forward, I lost headroom. I also lost any hope of having the seat base stay angled back for proper "butt cup." The absolute best I could do was to tip the seat forward to the brink of head clearance, and I STILL had to fabricate a 2.5" spacer for my steering wheel quick release. I had perfect reach now, but my seat base was still flat, which caused me to slide out when experiencing periods of spirited driving.

And so... I cut the sides of my expensive Kirkey Road Race Deluxe, taking out a pie shaped wedge and pulling the sides together and rewelding them. I did this by simply measuring the gap under my thighs to the seat base, and removing enough material to bring the seat base in touch with them. That was the last puzzle piece. When I was done, wouldn't you just know it? I measured the angle, and found I had made a custom 10 degree RR Deluxe. Hmmm....

I sense "lights" coming on.

Geo

I've been following this with interest. I actually am (perhaps) one of the oddballs who actually likes driving/racing in a semi-reclined position. I really feel I can get a better feeling for the car that way.

So, I really don't see the issue here, although I can feel for those who like a more upright seating position. To me the solution is a very simple one - extensions, just as you have done John. You have the solution. It's a perfectly acceptable one. It's one I have taken. Our QR moves the steering wheel 2" closer to the driver and in our Sentra SE-R I eventually installed an additional 1" spacer for better leverage on the wheel and couldn't have been happier. As I am still building (actually, at the moment, dismantling) my 944 I don't know exactly where I'll have everything, but I'm quite sure I'll have spacers as part of the seating/controls solutions.

You're a good fabricator John. You have the solution. It's perfectly acceptable. If you are looking for a more elegant solution, I can provide it, but I doubt you need help. I just have an off-the-shelf solution (at least for the 944) if you'd prefer one.

RedlineMan

Yeh... we're taking this way off topic, but...

OK, G - You have spurred me to rephrase and clarify further. You like a reclined seating position, but you still like decent reach to the wheel for leverage. Certainly nothing like A930Rocket's pics I wouldn't suppose. Once you get much past 6'2" you start to run into headroom issues that do not allow you to tip the seat forward any farther, and so you must look to extend the wheel hub to improve reach. Not necessarily that difficult, and perfectly accceptable as you state.

What do you do in the case of the same scenario in a dual use car with full column equipment and air bags? Say a 996? The slope was already slippery. It's now GREASED!

The only reason I keep bringing all this stuff up is to inform folks that A) Knowing all the aspects in play here is tough, and getting a seat to fit all parameters properly is not as easy as it may initially seem. B) Getting it into a car without having to hack things up is an order of magnitude more difficult. C) Factoring safety concerns in jumps us up the difficulty scale yet again.

Being an under-85th-percentile-person definitely has advantages!

Bull

I would not:

1. drive in the position pictured.

2. hack up the car and seat to make it work.

3. Compromise safety for comfort/convenience

So, again I suggest that for those who want to see how I overcame all of these issues in a 993, while being 6'5" and 290+lbs, stop and take a look at my car at Mosport 8/21 - 8/24. No cutting, no 20 degree layback, no straight arm driving...but no sliders either!

If they don't work for you DON'T GET THEM!

jgrant

When I was down at the PCA DE at Portland a few weeks ago, one of the instructors was easily 6'3"+, and had actually fashioned a fibreglass "addition" to the roof of his white 951. He'd cut a whole in the roof and put a little white fibreglass bubble over it to give him an extra 3-5" headroom.

Not the ideal solution for some, but it looked great and worked even better.

A930Rocket

WOW. I should have used a different picture..... LOL

That was just a good picture of the seat, not me and my driving position.

For driving, my arms are down more and my hands are on the wheel at 9:30 and 2:30.