Seating/Roll Bar Height Concern - Need Some Help

[Xusia]

Xusia, many guys are like me and take only a brief note of suggestions, or ignore them entirely, if they are not ready for that part of the build. I'll bet you've done that, too. Later, however, I go back and read it carefully when I'm into that part and understand what's happening. You'll find some guys months from now pasting in a link to your video to help somebody asking about making the OE seats work. It's all just a big ocean of info that we dip into when needed. Keep posting your innovations, please.

Good point Pete, and thanks for pointing that out. I plan to post everything I do, in case it is helpful. I guess I was just very excited about this and expected others would be as well. When NO ONE responded, it kinda took the wind out of my sails. No biggie in the grand scheme. I'm not quite done modifying the seat yet (fine tuning), and I will post a pic of me in the seat when I'm closer to done.

[RM1SepEx]

Yup, document all you can, hopefully others will take the time to wade Through the old build posts for answers... That's why I do it too

[FFRSpec72]

So with all the various folks having issues with fitting in the 818 and having to do all these odd things to fit, so I compared my 818 "R" with my MKII Challenge car and the winner is:

(1) Floor to top of rear roll cage bar, challenge = 41" 818=41"
(2) Floor to highest point on side roll cage bar, challenge=34" 818=34"
(3) Center console to side, challenge=21" 818=21"
(4) Front firewall to rear firewall, challenge=54" 818=55-6.5" (for fuel tank) 48.5"

So the interior room is about the same except the 818 has 5.5" less leg room if you move the firewall back and use a 6.5" (or less) wide fuel tank. I will gain the most of the 5.5" back as I have a 20 degree layback seat in the challenge car (which uses 8") and will use a 10 degree layback seat in the 818 R (which uses 4.5"). So for me (6'0 and 175lbs) it will be an even swap and I have no issues with the room in the challenge car.

[Grintch]

So much for the promised, wookie compatible, increased interior space.

Looks like I will be shopping for a C6 and just selling or trading in the STI.

[wallace18]

So much for the promised, wookie compatible, increased interior space.

Looks like I will be shopping for a C6 and just selling or trading in the STI.

I am 6'3" and have tons of leg and head room with Kirkey seats. It is all about what you use to get what you want. The C6 will be a better everyday car for sure,

[Xusia]

I agree with Wallace - it's all about what you use. My case was unique to me. And I should point out that with a little elbow grease, I'm making the stock seats work. I also think there is room for FFR to design an optional pedal box that could yield some additional leg room. I don't know if the wilwood pedal box offers more room or not.

In summary, sure, there is room for improvement, but you DO have options to make yourself fit.

[Goldwing]

Great work Brian! I'm very happy to see the progress. Great choice of a model to display your work! I only started to tear into the stock seat a bit and also picked up an aftermarket seat to compare. There is another guy local to me who is bigger than me and very interested in gaining extra room as well. We've been putting our heads together a little on it, but he's just now picking up his kits. Since the aftermarket seats are reasonably priced, I don't feel as bound to maintain sell ability of the stock seat, so I'm feeling bolder about tearing them apart. Compared to the aftermarket seat (Procar) the stock seat has a little extra height for head protection against the roll bar. At least I thought so until your video. I guess I'll need to see where the back of my head sits after working on the stock seat. With the Procar seat, I think a roll bar pad and cover is mandatory. Nice work.

Kit Aircraft builders will cut wing foam with a hot wire to shape before fiberglassing. Makes me wonder if there is a DIY version we could use on the seats or if the foam is cuttable in that manner. Makes for a clean cut anyway. Maybe Tahoe Tim will see it and have had experience with that?

[Goldwing]

You are just a little ahead of me, after my ankle sprain sidelined me. Without my firewall finalized (2days ago), I felt not enough was nailed down to focus on the seat itself. With the nice weather, i started coating the panels with sound deadener. Once I get the thickness up and it dries I'll be in a better position to offer meaningful help. For now, I'll cheer you on! My 2 year old has been a little upset with me that "her" seat is out of the car while installing the firewall and painting sludge, lol. She misses "driving."

[gpaterson]

The solution I have discussed with a local roll-cage fabricator is simple although it does involve some expense.

Neither the 818R or 818S can be used in Motorsport New Zealand events. The cage is required to have a front hoop and lateral bars to be sanctioned. Whilst the R appears to have both, it is not constructed in a way that MSNZ would certify it. So the solution is to build a separate bolt on cage that can be used on the track. In a ordinary tintop it is permissible to bolt the cage to the rear parcel rack and front firewall under MSNZ regulations. What I am suggesting here is doing just that.

The approach involves cutting the existing roll-bar off (I am planning on using an S), remounting it on 3mm plates and bolting back on - this allows the car to be used as intended and leaves open the use of a soft-top or hardtop if one is developed. For track use the street roll-bar would be unbolted and the compliant roll-bar bolted on which includes a taller rear bar, forward lateral bars and a hoop around the windscreen. This would be bolted on the rear 3mm plates and similar on the front firewall. This approach gives you a track compliant car and the flexibility of a road car too. Perhaps you might need two engine covers (one from the R and the other from the S) to be perfectly adaptable.

I have asked FFR not to weld the rear roll-bar onto my frame as it would be much easier to make the modifications before it was fitted but for 'safety and quality' reasons they have declined to do so!

Does this approach work with other certifying bodies?

[FFRSpec72]

Does this approach work with other certifying bodies?

An S would never be allowed to run wheel to wheel without the proper cage, the R cage meets all the US sanctioning race bodies, I have had NASA, SCCA and ICSCC look at my cage and all gave a thumbs up pending my fit in the car.

I don't understand your approach since the S has no real front roll hoop, bolt on cages here in the US get really securitized and I don't see how you can add a front hoop to the S.

[Grintch]

Maybe the problem is they don't allow the low front hoop design?

[FFRSpec72]

Maybe the problem is they don't allow the low front hoop design?

Looking at the rules http://argent.fia.com/web/fia-public...penform&lang=a see article 253 I don't see why the R cage will not pass as it meet what is outlined in the FIA guidlines

[Grintch]

Looking at the rules http://argent.fia.com/web/fia-public...penform&lang=a see article 253 I don't see why the R cage will not pass as it meet what is outlined in the FIA guidlines

8.2.4 Front rollbar (Drawing 253-1) :
Similar to main rollbar but its shape follows the windscreen pillars and top screen edge.

This statement and the pictures tell me no low front hoops.

[gpaterson]

Am I looking at the wrong part of the FIA regulations? Article 253: section 8.2

As noted by Grintch above according to my reading of 8.2.4, where the vehicle has a windscreen the front hoop must follow the windscreen pillars and top edge. This means if you build a R with an windscreen then the front hoop on the standard R chassis does not comply with FIA regulations. Maybe I am wrong but if not it does have a impact on the guys that are building street/track cars.

Further, the safety cage cannot unduly impede the entry or exit of the driver or co-driver. This means that the R could never be used in events with a roof, particularly a hard-top, as the side-bars would substantially impede the entry/exit from the vehicle. The only way in and out is through the roof.

In regard to bolting into the car, the definitions clearly contemplate the bolting of the cage to the chassis according to 8.2.12 which states the cage footings can be bolted and/or welded to the bodyshell/chassis. Whilst in practice certifying bodies may eschew securing the cage by bolting (as I had proposed), the regulations seem to allow it.

In summary, for those guys who want to street-legal track car then the R chassis should be ok. In New Zealand it could be registered for use on the road without a windscreen. However if you want a increased level of comfort which includes a windscreen and eventually a hard-top then according to my research the R chassis will be problematic for track use due to the design of the cage (when fitted with a windscreen) and the difficulty of getting in and out (if used with a fully cage and especially a hard-top).

In my case I am keen to use the car for the New Zealand Targa event (see targa.co.nz). It is an extended tarmac rally run over closed roads in New Zealand, of which 2 of the 5 days are usually wet. Suffice to say it is not an event I would contemplate in a car that has no windscreen or roof (even a soft-top). So to use the 818 in such events I am looking at strengthening the S series (cage and side bars) rather than re-engineering the R chassis.

If you think I am on the wrong track please let me know.

[Grintch]

You can't have a cage that doesn't impede access somewhat. Espicially the FIA cages which seem to add a new required tube every couple of years. But you still have to be able to get in and out of the cars, especially out in an emergency in a reasonable time.

The production car rules may not be the best for the 818. Is there a set of rules for "specials"? Or you could try arguing that it's a sports racer. But you really need to talk with a tech inspector to find out what will work. But yeah, if the R cage doesn't pass muster, starting out with an S and cutting off it's roll bar is probably the best clean slate to start from.

[SnyderJD]

Rehashing an older thread... With the Kirkey's does anyone have any photos of them mounted? I dropped a low profile mount on some OMP WRC seats this weekend , and was a good couple of inches over the bar in my 818c. I have them mounted as low as possible. I'm only 5'10" with a 31" inseam... Hoping a different combination will get me lower.

[Hindsight]

From what I have seen, nearly all the racing seat brackets are about the same, and allow you to go so low that the bottom of the seat touches or almost touches the frame. In my case, even with a very thin Momo racing seat with momo brackets that were low profile, my head was still above the bar. The bar on the S is simply too low. In my case, and in Bob's case, we cut out our roll bars and fabricated new ones. I know that's not a very attractive option but it was the only option.

[flynntuna]

In the FFR galleries, the left hand drive 818s has kirkeys installed.http://www.factoryfive.com/galleries...-wilwood-818s/

[phil1734]

The factory five show car (the dark grey coupe) has Kirkeys. I sat in them when I picked up my kit a year ago and was surprised at how comfortable they actually were. I wouldn't road trip in them, but you could easily do 100 miles in them and not regret life the next day.

Either way, I would think that with the right bribe a phone call to FFR might field the answer you're looking for. It's a fairly simple measurement for someone to run out and check for you as long as the car is still in the showroom.

[Bob_n_Cincy]

Rehashing an older thread... With the Kirkey's does anyone have any photos of them mounted? I dropped a low profile mount on some OMP WRC seats this weekend , and was a good couple of inches over the bar in my 818c. I have them mounted as low as possible. I'm only 5'10" with a 31" inseam... Hoping a different combination will get me lower.

I have Kirkey 47900 intermediate road race seats (18" wide 15* layback) . They are bolted flat to the floor (x bracing) with no seat brackets. I should clean the windshield before I take pictures.
I'm 6" 32 inseam

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