Seating/Roll Bar Height Concern - Need Some Help [Archive]

Xusia

02-22-2014, 04:50 PM

Let's start with the GOAL: I want to be able to do HPDE (High Performance Driving Events) in my daily driver 818, so I'm trying to build to the general requirements.

The Problem:
In order to meet the requirement that my head be below the roll bar in a helmet (commonly referred to as the "broomstick" test), I apparently need a seat that places my butt NO HIGHER than 1" off the floor of the car.

Relevant Facts:
At less than 6'1", I am not that tall. I have a 33" inseam, so I don't think I am overly long in the torso either.

Even if a seat existed that would place my butt 1" off the vehicle floor, I'm not putting such a seat in my car. It doesn't meet my other requirements. Also, at least one of the HPDE organizers had a requirement that the roll bar had to be 2" above the top of the helmet. I can't meet that requirement even if I sit on the floor!

The Question:
So what can I do? Here's what I've come up with thus far, and I don't really like either, so this is what I need help with:

Just forget about using the car on a track. I can probably get plenty of joy from the back roads around here. <sigh>
Replace the roll bar with a taller one. But if I do, it might look dorky. Also, this might jeopardize my use of the soft top. Or being able to go coupe with it in the future (Would a removable roll bar meet requirements? If so, then I could use the taller one only on the track).

Based on what I'm seeing, I just can't believe anyone over 6' tall is going to be able to pass the broomstick test - with ANY seat. How are you all doing it?!?

HELP!

ClemsonS197

02-22-2014, 05:14 PM

You can get Kirkey seats and bolt them directly to the floor. Should put you about 1" off their floor with the foam cushion.

Santiago

02-22-2014, 05:27 PM

Xusia, may I ask how you measured your current clearance?

I only ask because some seats are built with a steeper back incline, making you sit prouder in the car (and of course, some are adjustable). Kirkey has/had 10 deg, 15 deg, 18 deg, and 20 deg seats. So I would also make sure you factored that into your clearance.

Best,
-j

RM1SepEx

02-22-2014, 05:36 PM

seat pan angle and seat back angle are key

I also feel like the cockpit does not have enough room, esp with the factory five tank... Being 5' 8" I can deal with it.

The tank should go up the center of the car...

The roll bar could easily be a couple inches higher. And as a kit you could do those modifications if you so desire...

Xusia

02-22-2014, 05:57 PM

Regarding seat angle, with the seat as far forward as allows (because of the cross bar), my legs were very cramped and I was still too high. So I tried sitting on a board, which allowed a wide variation in back angle. That's when I discovered I could be no more than 1" off the floor with ANY position that was at all comfortable.

Xusia

02-22-2014, 05:59 PM

You can get Kirkey seats and bolt them directly to the floor. Should put you about 1" off their floor with the foam cushion.

Thank you for the response. I don't want fixed position seats for a variety of reasons. Also, 1" of foam padding seems woefully inadequate for a car I'd like to drive daily and take trips in. :(

wleehendrick

02-22-2014, 09:32 PM

I'll second that seat angle with a thinner tank is key...

I just finalized my ergonomics today; got the steering wheel location dialed in (I used the aft mounting holes for the column dropped about an inch, an NRG short hub, 1/2" spacer and 320mm wheel). Picked a spot for my VCP/K-tuned shifter and Lokar e-brake handle, and got the seat height/tilt/location chosen. Due to an old back injury (30deg compression fracture on T6) I much prefer to sit reclined. I adjusted the side-mounts for my NRG seats to give the desired recline.

So, after all that, the end result is that I have plenty of leg room and my head is at least 2" below the roll bar (without a helmet on) and I'm about the same size as you. This would not have been possible with the FFR tank, I have about 1/2" of clearance to my firewall, which is moved back more than 2" with the Boyd tank. I am using fixed back shell seats mounted very low, but from my experience, firm seats set up right are more comfortable than a cushy sofa that sags and doesn't offer support. If I need a bit more comfort, I can always change the foam... 1" of the right viscoelastic material (memory foam) can do wonders.

I am now extremely happy with the location I have dialed in for everything... since it's built around me, it's a better fit and more comfortable than a luxury car with dozens of adjustments.

Good luck!

Lee

Xusia

02-22-2014, 11:05 PM

wallace18

02-23-2014, 07:34 AM

I have no gas tank and am actually planning on putting mine up front, so space behind the seats is no issue. Comfort isn't the only reason I don't want fixed seats - I'd like for others to be able to drive it as well (my wife, for one). My wife is 5'2", so if I mount any seat in a fixed location, that precludes her from being able to drive it. Not acceptable for me.

I'm looking for solutions that allow for seats with sliding rails and a recline function. If that just isn't possible, then I'll just give up on my goal of going to the track. I will NOT be using fixed seats.

If you can find someone close by with the Kirkey seats I suggest you sit in them before you condemn them. They are very comfortable for a racing seat IMO. I have raced in 6 hour endoro's and not had a complaint. They may not be your cup of tea but at least give them a try. JMO. Best of luck to you for a seat that works for you.

DodgyTim

02-23-2014, 07:49 AM

26447

These hoop additions wouldn't be legal for my local track, but you could ask

wleehendrick

02-23-2014, 10:54 AM

My wife is 5'2", so if I mount any seat in a fixed location, that precludes her from being able to drive it.

At 5'2", I'm sure you'll have to cut the cross-member out in order for her to completely depress the pedals. The way my seat is set-up, I have ~2 1/2" of space for forward travel. I may put a slider in, or I may just remount the seat closer for my 5'5" wife (my seat's side-mount's have multiple lower mounting holes). On the very rare occasions that she drives my Z, all she needs to do is move the seat forward a bit, so I'm hoping this approach works. She's been supportive of my build, but I told her if she wants to drive it she has to get her hands dirty and help... hasn't worked so far. :p

Santiago

02-23-2014, 12:05 PM

If you can find someone close by with the Kirkey seats I suggest you sit in them before you condemn them. They are very comfortable for a racing seat IMO.

Agreed. Looking at the Kirkey seats you would think they're torture devices. At least that's how I first felt. Then I sat in one. I do a lot of demo rides in my car and the last guy who sat in the pass. seat literally exclaimed in disbelief, "this is the most comfortable seat I've ever sat in." One Kirkey Intermediate Road Race Seat + 1" thick memory foam pad on the base = Comfy!

On the driver's seat I added wedges of foam here and there (sides/shoulders) to dial in the support for the tighter fit required for track duty. When I do a 3 hour road trip I just add a 1" stadium pad to the base (which I don't have under the cover because I want more seat feel on track, so less padding is better there). Even with a very stiff ride, the seat is surprisingly comfortable.

You can add sliders to any seat, but they'll typically bump you up 1" so that isn't always a feasible solution. Of course, style is every man's selection, so a Kirkey may not be the way to go but there are other styles of fixed back seats to consider.

On the bar side I'd like to see what someone comes up with in terms of raising the level of the upper bar on an S-car.

Best,
-j

VD2021

02-23-2014, 12:26 PM

Option 2 is what a custom project like this is all about.

I say go for it. You have all the help and advice right here for a very successful mod.

RM1SepEx

02-23-2014, 04:38 PM

I cut the front angled bar and added sliders.

I'm trying the stock seats, the tank location and shape UGH, the existing cockpit is far too small

the stock seat brackets provided now position the seat higher than the ones that went to SEMA in 2012, the car they wouldn't let us sit in. Thank god I'm the tallest in my family at 5'8". I redrilled them to lower the seat an inch but my sliders add 3/4 back

There should be room w/o the tank behind the drivers seat. I think that if you are creative you could do soln. with acceptable fuel capacity and improve weight distribution. I'm thinking a combination of a tunnel tank and a behind the seat tank allowing maximum seat travel

Goldwing

02-23-2014, 06:35 PM

The more threads on this topic I read, the more I fear the stock seats will not work. I want sliding and reclinable seats as well. At just shy of 6 feet myself, I'm going to have to watch the roll bar clearance if I want to do track days. I haven't entered that world yet, but hoped to with this car. I am waiting, for now, to see what FFR's new tank does for room, but if its a split design, as rumored, adding room to the driver's side only, the firewall is going to be a pain to modify. (I.e.: not just a simple bend). The Boyd tank is starting to look really attractive, but will aftermarket seats also be required? Ugh, it's looking likely.

Regarding roll bar extension. There is a whole wall of steel bars underneath the top roll bar. Seems it would offer plenty of cantilevered bolting locations for a bolt on solution. Whether a hoop at the drivers side only or a full width bar, with welded on plate steel on front and back to extend to bolting locations below. Install for track days, leave off for factory top options. The bolt holes will be hidden out of sight. If you modified the factory bar, having a top doesn't necessarily have to be out. It might mean modifying a packaged solution, or making your own. I've toyed with the idea of trying to make my own, but that will be another winter project after I give FFR time to come up with their top options.

Xusia

02-24-2014, 12:33 AM

First of all, I really want to thank everyone who posted. It means a lot to me, and is one of the reasons why I love this community. I have decided on a direction, and am going post the details of my findings and my reasoning in the interest of helping those who will face similar issues. For those who don't want to read the details, I'm going with the stock seats (<gasp!>, I know!). For those who want the details, read on. (and I'm happy to address questions)

BUT, before we get to the details, let me post some feedback for FFR. You guys are great. I mean, seriously - who else could make such a kick *** car affordable and easy to build. I truly appreciate that. Really. Now that said, the 818 cockpit is too small. SERIOUSLY. I know I'm not the first to say it. It's also not ergonomic. I'm happy to provide more details if you want, but suffice it to say the fore-to-aft cockpit length is simply too short. And the gas tank makes no effective difference in this because at some point the top of the seat hits the frame (leaving plenty of space for a gas tank in that spot).

Oh yeah; Details... Let's start with the facts. I'm just over 6' tall, 33" inseam, and 180 pounds. I fit comfortable in every car I've ever been in, except for a DeLorean. Just doing some math here, 6' = 72 inches. 72 inches - 33 inches of inseam, leaves 39 inches. 39 inches just happens to be the distance from the top of the roll bar to the cockpit floor. I'm probably not a full 39" tall when seated (I'm about 38"), but you can start to see the problem and how important the lean angle is. Except that there isn't enough space to get a decent lean angle - hence the basis for my feedback to FFR. The top of the seat can only go back as far as the frame rail / roll bar, so any increase in seat angle pushes the seat bottom forward, which cramps the legs and increases knee angle. It's all related and not good news IMO.

I had a friend come over and we fitted both the stock seats and the NRG seats I bought in a number of ways. The pedals and steering wheel were mounted, and there was no gas tank, so we could get a good idea how each would fit. What I found was that the NRG seats only put me about an inch lower. In my case, not near enough. I also found that because of the angle of my knees, sitting a bit higher off the cockpit floor was more comfortable. It also put the steering wheel lower (at one point I was sitting low enough the steering wheel was literally in my face). I know you can lower the steering wheel, but sitting higher just plain felt better and more natural in this particular cockpit. I also found the stock seats more comfortable because the seat base was longer and had a steeper lean angle than the NRG seats. The stock seats also have a raise/lower function that my wife found useful when we had her do a test fit. These are the reasons I am going with the stock seats.

In terms of mounting, I have a plan that will basically put the sliding rails of the stock seats right on the cockpit floor, while being easily removable from within the car (no under car, or side access required). I am confident this will yield the most comfortable configuration for daily driving. The only problem is that head is slightly above the roll bar. Personally, I am not worried. Previous convertibles haven't even had a roll bar. Neither does my sportbike. So really, this is still safer.

So what to do about the track? For now, nothing. BUT I have left myself with options:

Replace the stock seat with a race seat if/when I want to do a track day. This is why i devised a seat mounting that allows for easy removal.
Modify the roll bar. I also had the idea of modifying it with a bolt-on solution and 2 options: Stock height and race height. Not sure if that would be OK or not. I'm not against permanently modifying the roll bar, but I want the the soft top to work. And I'm assuming here it IS taller than the roll bar, because if it isn't, well, I can't use it and won't be buying it.

These problems are only exacerbated as you get taller. How you carry your height does factor in (legs vs. torso), but I really feel that anyone over about 5"10" is going to be making some compromises when it comes to comfort to keep their head below the roll bar. Fixed mount race seats will get you low, yes, but I really found that position just too low - and it wasn't comfortable for me (and this isn't a seat issue - it's about your body being just too low in the car).

So would I call the 818 "wookie compatible?" I guess that depends on your definition of "compatible." I mean, there are ways wookies can "fit" but I don't see how they would be comfortable. So how important is comfort to you? (Or having your head below the roll bar?)

Goldwing

02-24-2014, 12:57 AM

My thoughts with the stock seats were also to mount it directly to the floor, but I hadn't fully worked it out yet. Removing the brackets below the slider and mounting the slider to the frame or an equivalent . What did you come up with for attachment? You're a bit ahead of me, but I did just mount the pedal box and steering wheel. Time to start planning.

FFRSpec72

02-24-2014, 02:04 AM

Anyone tried these http://wedgebrackets.com/seat-brackets-home/ ?

K3LAG

02-24-2014, 09:26 AM

Xusia,

I'm also interested in how you plan to mount them. One of my options is also to put the OEM seat sliders on the floor with some brackets, but I hadn't gotten to planning the install yet.

Larry

Goldwing

02-24-2014, 09:40 AM

I hadn't seen those, something to keep in mind. It looked like you could just bolt the oem slider right to the car as long as you didn't use a bolt that was too proud that would interfere with the slider. Either directly, passing through the floor, not my favorite as it could get sheared in a crash, or using brackets to orient the bolts horizontally. That would be a custom setup. This is where I was eager to learn of Xusia's idea for the mount. A top of my head solution for the direct bolt through would be a button head bolt (inside the slider) to a special nut. I don't know the name of the fastener so I'll describe it. A washer with a welded and threaded sleeve as to have a very low profile under the car. Ideally, that sleeve would be the thickness of the square tube so as not to crush the tube.

DodgyTim

02-24-2014, 12:57 PM

It doesn't help you Xusia, but the R roll hoop looks to be higher than the S, perhaps FFR needs to consider an option on the S order form of "S chassis with R hoop"

The S
26476

The R
26477

Xusia

02-24-2014, 04:16 PM

Anyone tried these http://wedgebrackets.com/seat-brackets-home/ ?

I have not tried those, but the various options I saw looked to have added height vs. mounting more directly to the floor. The slider mechanism in many of the pics looks very similar to what comes with the NRG seats, and will almost certainly interfere with the frame bar that runs between the center tunnel and the outside frame.

My thoughts with the stock seats were also to mount it directly to the floor, but I hadn't fully worked it out yet. Removing the brackets below the slider and mounting the slider to the frame or an equivalent . What did you come up with for attachment? You're a bit ahead of me, but I did just mount the pedal box and steering wheel. Time to start planning.

Xusia,

I'm also interested in how you plan to mount them. One of my options is also to put the OEM seat sliders on the floor with some brackets, but I hadn't gotten to planning the install yet.

Larry

I will try my best to describe my idea. I have nothing to actually show yet, but will happily provide that when I do.

On the seat side of the equation, I plan to remove the mounts that are attached to the sliders (i.e. where the bolts go that hold the seat in the car), and fit a steel plank to the bottom of the sliders that extends both fore and aft of the seat. <-- This is for easy access to the bolt from "above." There will be holes at both ends of the plank for bolts to go through - LARGE bolts! One thing to note here for anyone considering this on their own, is that the sliders are not level. If you remove the mounts as described above and set the seat on a level surface on it's sliders, it leans inward slightly. I plan to compensate for this by either using a washer or two when mounting, or by using thicker steel for the inside plank.

On the car side, I plan to weld a solid mounting bar or triangular plate (haven't totally decided yet) just behind the aforementioned frame bar that runs in front of the seat (on the inside of the "X" under where the seats sit). It will either be thick enough to be tapped, or I'll weld a nut on the other side. This will eliminate the need to have any access from below, while keeping the underside of the car tidy. It should also allow me to keep the existing frame bar that runs in front of the seats (I don't really "like" that bar, but I'm trying not to just cut stuff off...). I do not plan to use any of the frame for direct mounting because I don't trust rivnuts to hold the seat in place should a collision occur, and I don't want to go all the way through those pieces (i.e. with a bolt) because that means something on the bottom side of the car and I don't want that. My overriding goal (besides safety) is to keep it clean, simple, and easily accessible (such as for swaps).

I hope this makes sense. If not, ask away! :)

K3LAG

02-24-2014, 07:00 PM

The first half of your idea sounds the same as what I was thinking. I didn't realize the heights were different. I'll have to look at that more closely. I haven't decided how to mount to the frame yet.

Larry

Frank818

02-24-2014, 08:31 PM

Ok I see your point Brian. Maybe the guys at FFR are short? Who knows. Fortunately for me, that's a problem I probably will never have to deal with, tnx to the beauty of being 5'6", I can fit and sneak pretty much everywhere.

I guess an extension to the OEM roll bar or a tilted seat could be options? And how bad for you if you never go on the track by the books? I mean, you could still go on the track for the fun of it, on those tracks and events you don't need to respect regulations, right?

Other options, let's see... chop off your head, which I really don't suggest, or build your car with an F1 style seat orientation, which is almost 100% flat on your back. That way you could even "sit" (or lay down should I say) above the dash level, assuming the pedal box is installed "in" the dash.

Obviously, my options are jokes which aren't funny, cuz I wouldn't want to find myself in that situation, when all solutions don't seem to meet at least 1 requirement. :( But I am sure someone will guide you to something realistic. And how about tilting the seat, seriously?

Goldwing

02-24-2014, 11:54 PM

I pulled my driver seat back down from the attic today and noticed the different levels the sliders sit at. My memory left that out, lol. So, different size brackets/ bars, etc will be needed to level the seat, as you said. The back of the oem seat is pretty thick. I'm concerned that alone might push the issue, but I'm still game to try it. My only reservation is dismantling the brackets will make the oem seats more difficult to sell if I opt out in the end. Decisions.

Xusia

02-25-2014, 12:59 AM

And how about tilting the seat, seriously?

LOL - Frank you crack me up! To answer your question, the seat backs are tilted at an angle. I tried several angles, in fact. When looking only at the relative positions of head & roll bar height, increasing the angle is effective, sure. The problem, however, is that seat back very quickly hits the frame. This means additional angle can only be achieved by pushing the seat bottom forward. This cramps my legs, which are already bent quite a bit. So in essence it's a trade off between leg room and head height, and it only gets worse as you get taller.

Based on what I tried and what everyone else has said, I think the only solution that allows for adequate leg room with your head below the roll bar is a fixed position racing seat mounted basically directly to the floor. Based on people's feedback, this would probably be more comfortable than I imagine - from a seat perspective - but it doesn't address the other issues I had at such a low seat height. Your mileage may vary as they say..

I pulled my driver seat back down from the attic today and noticed the different levels the sliders sit at. My memory left that out, lol. So, different size brackets/ bars, etc will be needed to level the seat, as you said. The back of the oem seat is pretty thick. I'm concerned that alone might push the issue, but I'm still game to try it. My only reservation is dismantling the brackets will make the oem seats more difficult to sell if I opt out in the end. Decisions.

Something I found a bit odd is that I was able to get the WRX seat further back than the NRG seat. The reason is because of the shape of the NRG seat hit the frame and/or roll bar more easily than the WRX seat. Generally a lower back / smaller head rest is better (in terms of getting the seat further back), so if you don't want to experiment on the stock seats, you could try some other ones (armed with this knowledge).

I hope that helps you.

Frank818

02-25-2014, 07:47 AM

Brian, if you put the tank in the front, maybe you can modify the bars behind the seats and allow you to push backwards and tilt down the seats a little more, without cramping your legs?

wleehendrick

02-25-2014, 11:56 AM

Based on what I tried and what everyone else has said, I think the only solution that allows for adequate leg room with your head below the roll bar is a fixed position racing seat mounted basically directly to the floor.

Yup... that's my solution. Too bad it conflicts with your other requirements (something's gotta give). To me, this is ideal for the spirit of the 818... simple, custom, raw, track capable sports car.

I'm a stickler for ergonomics; a friend asked me how I can buy a car without ever driving or even sitting in it first. My answer was: 'the concept is brilliant and I'm building it around me, so it'll be right'. As I mentioned, I spent a good part of this past Saturday getting the steering wheel, seat, shifter and e-brake positioned. Since then, all my other cars (which are pretty well dialed-in) have felt a bit off! I'm now really, really happy with how it all turned out (well, I still have to mount my harnesses), but like I said it would not have been possible with the FFR tank, and stock seats.

Bob_n_Cincy

02-25-2014, 12:31 PM

The problem, however, is that seat back very quickly hits the frame. This means additional angle can only be achieved by pushing the seat bottom forward. This cramps my legs, which are already bent quite a bit. So in essence it's a trade off between leg room and head height, and it only gets worse as you get taller.

Xusia
I went through the same exercise back in October.

26494

criteria:
Legs not cramped
head below roll bar
eyes above steering wheel
comfortable

Considered solutions:
1. Move pedal box forward 2-3" (designed but not installed yet)
2. Move steering wheel forward (will do)
3. mount kirkie seat on floor (done)
4. Reshaped seat (done)
5. move gas tank to front of car. (doing, the Boyd tank is 2" to thick)
6. lengthen cockpit (not doing, but still on the table)
7. 1.5" spacer to lower steering wheel.(done)

26495

These are the kind of things that have really slowed my progress.
For my 5'4" daughter to drive, I will use a seat insert.

I guess I'm bigger than a wookiee
According to http://starwars.wikia.com/wiki/Wookiee They are 6'10" average
Bob

Xusia

02-25-2014, 03:30 PM

Brian, if you put the tank in the front, maybe you can modify the bars behind the seats and allow you to push backwards and tilt down the seats a little more, without cramping your legs?

That bar seems like a key structural component to the frame. I thought about modifying it for about half a second, but quickly dismissed it after that!

Xusia
I went through the same exercise back in October.

26494

criteria:
Legs not cramped
head below roll bar
eyes above steering wheel
comfortable

Considered solutions:
1. Move pedal box forward 2-3" (designed but not installed yet)
2. Move steering wheel forward (will do)
3. mount kirkie seat on floor (done)
4. Reshaped seat (done)
5. move gas tank to front of car. (doing, the Boyd tank is 2" to thick)
6. lengthen cockpit (not doing, but still on the table)
7. 1.5" spacer to lower steering wheel.(done)

26495

These are the kind of things that have really slowed my progress.
For my 5'4" daughter to drive, I will use a seat insert.

I guess I'm bigger than a wookiee
According to http://starwars.wikia.com/wiki/Wookiee They are 6'10" average
Bob

In the long run, I think modifying the pedal box is the way to go. Early on I toyed with this idea, but it seemed fairly complicated because of the proximity of the LCA mount, clutch pedal tavel & clearance, and a horde of other issues. I think what's really needed is different pedal box (but one that mounts on the firewall or from under the dash, because floor mounted won't work with the LCA mount location) that has a different pedal shape/structure so that it can clear the LCA mount while mounted further back. If you come up with something, PLEASE let me know. I will certainly still consider it.

Grintch

02-27-2014, 01:43 PM

Actually the broomstick test is a much harder test. It involves checking to ensure that the helmet head remains below a line from the main hoop to the front hoop. This is typically a much harder requirment than getting the helmeted head 2" below the main hoop. But as an S doesn't really have a front hoop, and full cages with them are only required for racing the broomstick test is not an issue for you.

One key thing with a more reclined seat is that the seat bottom needs to "recline" as well to be confortable. Think of how the seat bottom on a rocking chair "reclines" as the chair rocks back. If you just recline the seat back of a normal street style seat, it gets uncomfortable rather fast. But if the entire seat is tilted it stays confortable longer with more recline. And you don't end up with your legs flat on the floor with a low mounted seat.

Xusia

02-27-2014, 04:44 PM

One key thing with a more reclined seat is that the seat bottom needs to "recline" as well to be confortable. Think of how the seat bottom on a rocking chair "reclines" as the chair rocks back. If you just recline the seat back of a normal street style seat, it gets uncomfortable rather fast. But if the entire seat is tilted it stays confortable longer with more recline. And you don't end up with your legs flat on the floor with a low mounted seat.

Absolutely. This is an area where the WRX seat was superior to the NRG seat. It had a steeper recline and was therefore more comfortable.

custome

02-27-2014, 05:16 PM

I have some ideas about roll bar mods that involve a street version and a track version as you stated above. I'm 6'-3" with a 32" inseam so we'll have to "bend" that broomstick a little! :)

flynntuna

02-27-2014, 08:04 PM

I have some ideas about roll bar mods that involve a street version and a track version as you stated above. I'm 6'-3" with a 32" inseam so we'll have to "bend" that broomstick a little! :)

Like this one?

BC Huselton

02-28-2014, 08:45 AM

07FIREBLADE

02-28-2014, 01:04 PM

Pics??

Xusia

02-28-2014, 04:02 PM

I was under the impression that a bolt on roll bar addition was not permissible. If it IS permissible, then I would absolutely do it for track days.

Grintch

02-28-2014, 04:07 PM

Is it impractical or structurally impossible to add a second bar to supplement the top of the current S roll hoop. This second loop could add 2" sleeved in with an additional grade 8 bolt plate. it would look like the R bar and come up both sides of the S hoop with two additional vertical 2" bars directly over the Helmet site. All Grade 8 bolt in. It may be ugly for racing, but meets specs and makes all the other options for passing the Broom Test unnecessary.

We did this for the Ford Spec Racers to pass new requirements. Perhaps it is an option here...what am I missing other than UGLY?

BC

It's an old joke that the SRF roll cage is only legal because it is made by the SCCA.
The orginal main hoop height was apparently designed for female gymnists, but they already had a couple hundred frames build (and more on back order) before they figured out anything close to an averge size american male wouldn't fit.

Note that the "tallman kit" add on is welded in place, and includes new front and rear brace sections (hard to see in this photo), and even this would not be allowed on any other car. Racing rules require the main hoop be made from a single piece of tubing.

NASA 11.4.7 [HPDE requirement]
All open cars should have a roll bar installed to help protect the occupant(s) from injury during a roll-over. The
main hoop shall be one continuous piece with smooth Mandrel bends with no evidence of crimping or wall
failure.

The really weird thing is all SRF still get made with this double decker main hoop rather than replacing it with a simpler, lighter, cheaper, and probably safer once piece design of the proper height.

Xusia

02-28-2014, 04:09 PM

So what about NOT racing - just HPDE? Is an add-on generally permissible?

Santiago

02-28-2014, 04:23 PM

For HPDE your bar doesn't have to meet the wheel-to-wheel requirements. For that matter, it doesn't have to do so for Time Trial as well. This isn't to say you should feel good bolting on any ole' bar configuration you dream up or find...*cough*Autopower*cough*... just that you don't have to meet all the rule requirements.

I use a Maximum Motorsports bolt-in roll bar in my Mustang (I run NASA Time Trial), and it is very well designed and built. The keys to this are mainly how they tie into the existing structures, both in terms of location and mating method.

Best,
-j

Xusia

02-28-2014, 04:30 PM

OK. Wow. If bolt on is an option, that will make this much easier (and make me very happy!). My father-in-law is an awesome fabricator, so any roll bar addition would be completely custom [over] built.

BC Huselton

03-01-2014, 08:48 AM

What I was envision was the "Mating Method" as you describe it here. There are bolt in roll bars throughout the SCCA that meet standards. This should be doable by a savvy structural designer...I am not. My motive was to surface it as an alternative to having to reconfigure so many other things to get our seating position below the S hoop. I will check with Maximum to see if they could configure something. Are there other competent designers to contact that might make this work?

"The main hoop shall be one continuous piece with smooth Mandrel bends with no evidence of crimping or wall failure." Does this mean it cannot be bolted to or effectively secured in some fashion to the lower hoop structure?

BC

Santiago

03-01-2014, 09:09 AM

Maximum Motorsports is strictly Mustang focused. Couldn't hurt to ask, but I would bet they'll take a pass on such a project.

For any safety project that you need to pass a specific rule, you really should get in touch with the organization writing the rules. Someone there will be in charge of the series you want to run, and they are the definitive answers to what does or doesn't meet the requirements. For something like HPDE most of the race-series rules just don't apply.

Personally, seems like the big challenge for some sort of add-on raised bar is going to be getting it to fit within the available body openings. Looking forward to seeing what folks come up with.

Best,
-j

Goldwing

03-01-2014, 11:52 AM

My father-in-law is an awesome fabricator, so any roll bar addition would be completely custom [over] built.

I guess you'll have to decide how much he likes you first, lol.

Grintch

03-03-2014, 11:41 AM

So what about NOT racing - just HPDE? Is an add-on generally permissible?

The quoted rule WAS the HPDE rule. So no welded on or especially bolt on extensions. While track day rules get you out of a full cage, being 2" under the main hoop, and the broomstick test. They don't avoid the one piece main hoop requirement. The NASA TT safety requirements are the same as HPDE, but the SCCA ones are a bit stricter.

Basicly you need to modify the driving position so you fit under the main hoop, or you need to cut off and replace the stock roll bar with a taller one. Even for autocross, in the Modified classes, you need a proper, 1 piece main hoop. Although this probably wouldn't be enforced at many local events.

Xusia

03-03-2014, 11:51 AM

I'll keep my eye open for "less safe" HPDE events (<-- joke here, people!), but for me that effectively means "bye, bye track!" I guess I'll have to settle for tracking my "much safer" sportbike... :(

Grintch

03-03-2014, 04:40 PM

This is why I have been questioning the height of the roll hoops since the prototypes were built. Especially for a car that was supposed to be "wookie" compatible.

Canadian818

03-16-2014, 09:53 PM

I really hope the broomstick rule isn't strongly enforced here. This pic is with no cushion/foam on the seat.

http://i1113.photobucket.com/albums/k519/pope83/CIMG1880.jpg (http://s1113.photobucket.com/user/pope83/media/CIMG1880.jpg.html)

And the seat couldn't possibly be lower without cutting the bars.

http://i1113.photobucket.com/albums/k519/pope83/CIMG1883.jpg (http://s1113.photobucket.com/user/pope83/media/CIMG1883.jpg.html)

Santiago

03-17-2014, 07:18 AM

The quoted rule WAS the HPDE rule. So no welded on or especially bolt on extensions.

Basicly you need to modify the driving position so you fit under the main hoop, or you need to cut off and replace the stock roll bar with a taller one. Even for autocross, in the Modified classes, you need a proper, 1 piece main hoop. Although this probably wouldn't be enforced at many local events.

You need a proper 1-pc main hoop 2" over your head. That doesn't mean you MUST cut off the stock bar. You only need to do this if you cannot package an additional bar (basically another 4-point bolt-in bar) that meets the requirements. That is, if you can manage a different hoop that can be bolted into the car and removed for street duty, then you can leave the existing bar alone (and run a FFR soft-top, or whatever you're into on the street). What you cannot do (and I wasn't recommending) is that you try to bolt on an extension to the existing hoop. So if that's what Xusia meant by "add-on" then no, that won't fly. My point was simply that a bolt-in bar satisfies HPDE rules, not that a bolt-in appendage does.

The difficulty with what I suggested (also stated earlier) is that you need to be able to fit this additional bar around the existing body work. For many S-car owners, that's going to be a challenge as they may not want to modify their bodies, and I suspect they'll need to do so in order to allow another 4-point bar to bolt in. My thought was that another 4-point bar could be easily added just behind/outside the current bar - but you would need to clearance the area around the upper intake vents. A creative person could do this in a fashionable way - a quick and dirty way would be a carbon panel that matches the factory lines but easily unbolts for installing the bar. A harder way would be to recess a panel into the existing lines and paint to match the car.

I do agree, however, that preserving the body as-is means cutting the existing bar and welding in a new one that's high enough to pass tech. I also agree with Grintch that you'll likely pass tech anyway at many events - not that you should, just that you probably would.

For reference, how tall is Canadian818?

Best,
-j

Canadian818

03-17-2014, 07:29 AM

6'2 in the morning :)

gioguy21

03-19-2014, 12:06 PM

Hi guys, (extreme newbie here) i'm doing research before pulling the trigger and have been wondering about my height. i'm 6'3" 225. how hard is it going for me to fit in this thing?

Xusia

03-19-2014, 11:42 PM

I'm not sure if you've read this entire thread, but the answer to your question depends on how you define "fit." It depends somewhat on where your height is (leg vs. torso), but if you are "average" I'd say you are likely to find a way to be physically able to drive the car, albeit the position probably won't be comfortable.

Goldwing

03-19-2014, 11:56 PM

Try to get to factory five and sit in one of their cars or watch for their auto show circuit (I caught them at Carlisle, PA for the kit car show). At your height & weight, you're probably like me in that most sporty cars don't fit well, and I'm 3" shorter, just broad shouldered. There are mods that will help starting with a thinner fuel tank, moving to a thinner low profile seat, and finally some are looking at moving the pedals forward as well. The tank and seat are easy, but cost money. The pedal box will be more difficult, but inexpensive if you're good at fabricating. You'll laugh, but use "wookie" as a search term to find threads and posts on the topic.

gioguy21

03-20-2014, 08:41 AM

lol @ "wookie"...thanks guys for the input

Grintch

03-24-2014, 05:58 PM

You need a proper 1-pc main hoop 2" over your head. That doesn't mean you MUST cut off the stock bar. You only need to do this if you cannot package an additional bar (basically another 4-point bolt-in bar) that meets the requirements. That is, if you can manage a different hoop that can be bolted into the car and removed for street duty, then you can leave the existing bar alone (and run a FFR soft-top, or whatever you're into on the street). What you cannot do (and I wasn't recommending) is that you try to bolt on an extension to the existing hoop. So if that's what Xusia meant by "add-on" then no, that won't fly. My point was simply that a bolt-in bar satisfies HPDE rules, not that a bolt-in appendage does.

The difficulty with what I suggested (also stated earlier) is that you need to be able to fit this additional bar around the existing body work. For many S-car owners, that's going to be a challenge as they may not want to modify their bodies, and I suspect they'll need to do so in order to allow another 4-point bar to bolt in. My thought was that another 4-point bar could be easily added just behind/outside the current bar - but you would need to clearance the area around the upper intake vents. A creative person could do this in a fashionable way - a quick and dirty way would be a carbon panel that matches the factory lines but easily unbolts for installing the bar. A harder way would be to recess a panel into the existing lines and paint to match the car.

I do agree, however, that preserving the body as-is means cutting the existing bar and welding in a new one that's high enough to pass tech. I also agree with Grintch that you'll likely pass tech anyway at many events - not that you should, just that you probably would.

For reference, how tall is Canadian818?

Best,
-j

Is there room to bolt in a new roll bar without cutting off the old one? I can't think of a case where there was a good mounting point available with a non compliant "style bar" already in place.

metalmaker12

03-24-2014, 06:21 PM

Hi guys, (extreme newbie here) i'm doing research before pulling the trigger and have been wondering about my height. i'm 6'3" 225. how hard is it going for me to fit in this thing?

I am 5'9 so no big help, but if you mount a thin seat to the floor ( kirkey style) and use the Boyd tank and push the firewall back to the tanks edge you will fit no prob. Tom (Wallace) is pretty tall ( like 6 something) and he fits

AZPete

03-24-2014, 10:37 PM

Gioguy21, I'm 6'3" with 32" inseam, 235 lbs. and I fit, but I made a few adaptions. Installed the Boyd tank and moved the rear firewall back 3". I cut the bottoms of the OE seats to get them lower, which works for me but you could get even more space with Kirkey seats. Also, there's a very important improvement over the FRR roadster that is key. In a roadster there's no way I can get out while seated because the door hinges are by my knee. In the 818 the door hinges are much more forward, almost to my ankle, so I can get out with my butt in the seat. Why is that important? Because in the 818 I don't have to raise my body straight up to get my left leg out, as in the roadster, which means I can buy the 818 soft top, drive in any weather and have air conditioning. Foot room and head room are good but the length of the door is also very important for tall guys! Yes, you'll fit.

mekohler

03-25-2014, 08:30 PM

I am 6'3" and I went with a fixed NRG seat, Boyd tank. I took the brackets on the seats and made the rear of the butt of the seat as low as possible, and tilted the front of the seat up a couple of holes. I now have several inches of clearance. I had to elongate the mounting holes to allow the recline angle I am using. I might of even flipped the brackets to get the rear lower.

Santiago

03-25-2014, 10:03 PM

Is there room to bolt in a new roll bar without cutting off the old one? I can't think of a case where there was a good mounting point available with a non compliant "style bar" already in place.

I can't speak to other cars, since I wasn't looking over those candidates. However, for the 818S I do think one could fabricate a mounting base just to the side of the existing bar. The S-car's main hoop bars land right at the end of the frame, so if you were so inclined you could readily fabricate a flat base just past that (i.e. further out laterally) to which you could bolt in a bar (properly gusseted). Of course, this sends the bar through the plane of the horizontal section of the forward quarter panel. The down bars heading back would also land you afoul of the same area (only further back), so you'd end up having to come up with a removable body panel that might look something like the carbon fiber one that the early Blue R-car had in that area.

Definitely not an option to everyone's liking, but do-able.

Best,
-j

Goldwing

04-07-2014, 11:34 AM

Well, I finally relented and accepted that the stock seat won't work for me. The cockpit is too small. I'm experimenting with Procar sportsman Pro 1615 (http://m.summitracing.com/parts/sca-80-1615-51). I'm using the Boyd tank, and I'll modify the firewall to help. For the firewall, my plan is to bend the lower portion of the upper piece further about 12*, then cut the "shelf" in half and overlap the pieces to thin the shelf. At this point, either my legs are happy or the recline is about right. Still not enough room for both, but it'll have to do unless I get ambitious enough to follow others with a pedal box mod. I'm trying to decide between mounting the slider level or at an incline. I need to use a spacer under the front of the seat to tilt the seat bottom, if I put the spacer under the track, I can lower the rear portion of the track, just a bit more. Has anyone had experience with the NRG seats and Procar's to compare them and offer an opinion? I'm lucky to have a Summit Racing close by to play with the Procar. Here's the Procar just thrown on the floor for reference:

27710

I sit just barely below the roll bar. I didn't look at adjusting the cushioning yet, as I'd like to keep this seat returnable.
Here's a pic of the planned firewall profile:

27711

Opinions? Foreseeable problems? Thoughts?

EDIT: Oh, for reference, I'm just shy of 6' with a 32" inseam.

wleehendrick

04-07-2014, 12:07 PM

I'm about the same size as you and went with NRG seats mounted on the floor. I was able to use the sidemounts to give a good recline and fit similar to your first photo, if not a touch lower; the harness holes are right at the level of the square tube. BTW, I bent the upper piece of the rear firewall an additional 16deg in a press-break, IIRC. I also found that the steering wheel was too high, so I used some slightly longer SS spacers to drop it a bit more. I'm using a 320mm wheel, BTW, so knee clearance isn't a problem.

flynntuna

04-07-2014, 06:41 PM

RM1SepEx

04-07-2014, 09:07 PM

I'm curious, what is the measurement from the pedals to the front of the seat, from the pedals to the seat back and from the steering wheel to the seat back? At just under 6' myself, it doesn't seem that anyone over 5'6" will fit with the WRX seats and fuel tank.

5'8" fits... :mad: but no bigger with stock seats. And I did lower the FFR brackets, they were waaaay higher than they needed to be. :confused:

TahoeTim

04-07-2014, 09:22 PM

I'm late to the party but what was FFR thinking? I get the Cobra needing to look correct but why didn't they stretch the 818 a couple inches and/or raise the rollbar an inch? I never built a GTM for the same reason.

I don't get it.

Xusia

04-07-2014, 10:47 PM

We are ALL asking that question...

I'm hopeful this will be addressed in a future update. Or perhaps a version that's 3" longer: 2" in the cockpit, and 1" in the engine bay (for the EZ engines). 818L?

Goldwing

04-07-2014, 11:13 PM

I'm curious, what is the measurement from the pedals to the front of the seat, from the pedals to the seat back and from the steering wheel to the seat back? At just under 6' myself, it doesn't seem that anyone over 5'6" will fit with the WRX seats and fuel tank.

Brake pedal to seat front (in modified position): 19-1/2"
Brake pedal to rear seat cushion ("): 39-1/2"
Top of steering wheel to seat back: 29"

On the last measurement, I have a pretty good fit here. With my arms straight, I have a good hold of the steering wheel, it's a good fit in this position, one where I likely won't shorten the steering wheel. This Procar seat has a pretty deep lower cushion, so take the first measurement with a grain of salt. Without modifying the firewall or tank, those numbers would be 3" smaller. I have a nice clutch pedal feel in this seat position, but I may move the gas pedal a bit forward for long drive comfort.
Taking a few measurements, the uncompressed Procar seat is giving an extra 2" rearward at the bottom, and 3" at shoulder level. It's less drastic sitting in it due to the factory seat being very compliant while the Procar seat is much firmer. Still noticeable, just not 3" drastic, the seat height going to the aftermarket seat is much better IMO. I'm going to check the height on the NRG seatback, my head is close to the rollbar, while the crown of my head sits even with the top of the seatback. The factory seat gives my head and neck pretty good protection from the roll bar and from whiplash.

Goldwing

04-07-2014, 11:21 PM

Wleehendrick, can you measure the seatback from the bottom cushion to the top of the seatback on your NRG? The Procar is 31-1/2", I could use a bit more height ideally. On the firewall. I had planned on doing just as you did, but wanted to be sure the seat didn't get blocked by the shelf, so I'm grabbing an extra inch. I'm hoping stuff on the other side of the firewall is flexible on mounting position, lol. The steering wheel is factory, but has the height adjusters, so I have the movement I need. It would be nice if it truly tilted though.

flynntuna

04-08-2014, 08:49 AM

Brake pedal to seat front (in modified position): 19-1/2"
Brake pedal to rear seat cushion ("): 39-1/2"
Top of steering wheel to seat back: 29"

On the last measurement, I have a pretty good fit here. With my arms straight, I have a good hold of the steering wheel, it's a good fit in this position, one where I likely won't shorten the steering wheel. This Procar seat has a pretty deep lower cushion, so take the first measurement with a grain of salt. Without modifying the firewall or tank, those numbers would be 3" smaller. I have a nice clutch pedal feel in this seat position, but I may move the gas pedal a bit forward for long drive comfort.
Taking a few measurements, the uncompressed Procar seat is giving an extra 2" rearward at the bottom, and 3" at shoulder level. It's less drastic sitting in it due to the factory seat being very compliant while the Procar seat is much firmer. Still noticeable, just not 3" drastic, the seat height going to the aftermarket seat is much better IMO. I'm going to check the height on the NRG seatback, my head is close to the rollbar, while the crown of my head sits even with the top of the seatback. The factory seat gives my head and neck pretty good protection from the roll bar and from whiplash.

Thanks for taking the time to measure, those measurements are nearly identical to what I've got my DD adjusted at. The only difference is the brake pedal to seat back, where it's at 41.5". Looks like most people will be making the firewall mod.

philly15

04-10-2014, 10:52 AM

Just out of curiosity, what seats have people had the best luck with? I've held off ordering to see what works best. I myself am contemplating the corbeau fx1 pro, but wanted to get some last second opinions first. Pretty much anything should work for me I'm only 5'9" 180.

wleehendrick

04-10-2014, 11:03 AM

Mine are NRG FRP-300. I was leaning towards those Corbeaus, until I got a great deal on NRG seats from Erik. I would think they would fit similarly; pretty much any fixed back bucket with sidemounts that let you drop the butt down just above the floor, and tilt it backs seems to work well. For those around 6', moving the firewall back is also necessary for leg room, but you may not need to depending on if your height is in your legs vs torso.

Xusia

04-10-2014, 12:33 PM

I'm still working on my stock 2003 WRX seats, and I've made some progress. I've mostly solved the legroom problem, and have a plan to address the height problem.

I've completely disassembled the seat (not as difficult as it seems!), and believe there is actually room to get the seating position much lower. As always, I will post pics - and probably a video - when I get it worked out.

CU9DZ

04-10-2014, 02:06 PM

Yes I would vote for the 818L also. I have two sons who are 6'3" so need the car to fit tall people. I am 6' even. Have been reading all your comments about moving the seat back.

Xusia

04-13-2014, 01:42 AM

Also posted in my build thread; making progress on the seats: https://plus.google.com/107272488473870379365/posts/d4jbg8vNPSz

Xusia

04-15-2014, 11:06 PM

Wow. I really expected more folks to be excited by this. :(

AZPete

04-15-2014, 11:49 PM

Xusia, I appreciate what you've done. I also tried to make the WRX seats work so I cut lots of metal off the seat bottom, modified the FFR mounts and removed some foam. I got the drivers seat low enough that even with the head rest raised it's below the roll bar. I bolted directly to the frame and also put in a Boyd tank. But, a lot of guys want the seats to be adjustable or just want to buy aftermarket seats. The main reason I wanted to make the WRX seats work is that I can buy nice leather upholstery made for these seats. Maybe with your video (and cute daughter!) other guys will make the Subaru seats work. This photo was before I did the passenger seat. Quite a difference, eh?
28008

ehansen007

04-16-2014, 12:04 AM

I would say that if you're over 6-0 , you're going to have to have to get kirkeys or glass seats (where you're sitting no more than an inch off the floor) in order to get your head below the roll bar with a helmet on. Broomstick will be tough. There's a reason why the roll bar on the challenge car looks like a swing set; because it works!!! :)

28009

FFRSpec72

04-16-2014, 12:33 AM

Santiago

04-16-2014, 07:02 AM

Xusia, I just got a chance to check out the video - very cool mods to the OEM seat! I think this will be a major help to folks. The fact that an ultra-cute daughter is cheering you along only makes it better. =)

Best,
-j

FFRSpec72

04-16-2014, 02:17 PM

I have been playing around with the rear firewall for a fuel cell design and here are the measurements and angles that I came up with, these should also work with the Boyd tank (not sure of the slant on the Boyd tank though). This should work well with a 10 degree layback on the seat (as you can gain 4" over a 20 degree layback).

28028

AZPete

04-16-2014, 02:26 PM

Wow. I really expected more folks to be excited by this. :(

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.

Xusia

04-16-2014, 02:49 PM

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

04-16-2014, 04:11 PM

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

04-17-2014, 10:55 AM

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

04-17-2014, 04:14 PM

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

04-17-2014, 04:23 PM

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

04-17-2014, 11:58 PM

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

04-18-2014, 04:01 PM

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

04-18-2014, 04:09 PM

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

05-08-2014, 06:01 AM

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

05-08-2014, 10:44 AM

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

05-08-2014, 04:40 PM

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

FFRSpec72

05-08-2014, 05:49 PM

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

Looking at the rules http://argent.fia.com/web/fia-public.nsf/wcodj2012?Openform&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

05-13-2014, 08:55 PM

Looking at the rules http://argent.fia.com/web/fia-public.nsf/wcodj2012?Openform&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

05-20-2014, 10:23 PM

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.