TPNxl

Hey everyone,

I am a roughly 6'1" owner of a 2011 RX-8 who wants to get into autocross/HPDE events. I recently discovered that I cannot fit into my RX-8 with my helmet (I bought a RaceQuip open face SA2015 unit in size XL). I paid a shop to do a foamectomy to my seat (they removed roughly 2 inches of foam from the back portion of the seat bottom) but I still cannot fit.

My head is clear from the main portion of the roof but hits a sloped portion of the roof, forcing my head to lean right (see picture for more info). As such, I think my next best course of action is to buy something like a Kirkey seat and mount it in my car (planning to use a Planted Seats bracket). I'll probably have to add ballast to the seat to keep my car in SCCA Street Touring (I cannot run in SCCA Street AFAIK with this seat and I don't want to shell out a ton of cash for a car I might crash).

What do you guys think? Is this worth my time and money? Will there be other problems with this idea related to driving position? Should I just buy another car?

Link to head/roof diagram

Loki

iTrader: (1)

I'm about the same height and understand the problem. In addition to removing foam, you can get another solid inch by changing how the seat pan is attached to the rest of it. There's a DIY in the DIY section.
Long story short with some seat finagling and finding the right seating position, it's doable. Depends a lot on much of your height is legs vs. torso vs. neck. The size of helmet also makes a difference, a quarter inch here and quarter inch there adds up.

If you need to get new seats to enjoy your driving events, and you're just getting into the sport, it might be worth it to not worry about classing for now. With seats come headaches like seatbelts, cages, etc. The stock seat contains an airbag and sensors that you don't want to disable while going fast around a track without an adequate replacement for the restraint system you took out.

speed7

Seats in the Rx8 are tough. But I know a guy who managed to do a bolt in setup for his car. I’ll post an update tomorrow with the details. The secret sauce is in the seat rail kit you buy. After that I suspect any bucket seat will do.

oh and the planted seat bracket isn’t it. That’s what I tried first and it didn’t work.

Federighi

iTrader: (7)

I'm 6' tall and have plenty of head room with helmet running my Recaro SR5 on Bride rail bases, completely pnp. Recaro seats are an excellent option if within budget and in general fit without much trouble. You can take measurements of your torso and cross-reference with model dimensions listed from each manufacturer. Kirkey seats are also a great idea and I lol'd when I saw your drawing. You have a sunroof I take it?

Tillet will absolutely fit and is a very cool seat. Fit and finish are top notch. Highly suggest checking them out. And an oem Recaro from the r3 is another potential solution.

As far as maximizing the value of your dollar, you could easily purchase a 'prepped' track car and call it a day. Most likely for less than you'll have to spend outfitting a race seat. There're many options out there to choose from, some even championship winners if that matters to you. That way you can save yourself from the headache and enjoy all the fun.

Hope this helps!

https://www.tillett.co.uk/car-racing-seat.asp

TPNxl

@Loki thanks for reminding me that I can change the seating position, but I'm not sure that will give me enough headroom. Based off this DIY (DIY: You CAN lower the power seat! - RX8Club.com), it looks like you can gain about 1/2" of headroom by bolting stuff around. That might not be enough based off my seating position.

@speed7 That's interesting that the Planted bracket doesn't work for this purpose. Let me know what kind it is. I'll also be using a side mount system to mount my seat to the bracket.

@Federighi I do not have a sunroof or power seats (I have the Sport trim), but my helmet is so big (XL size) that I have a similar problem to sunroof owners. The reason I like Kirkey is because they're US based, very inexpensive, and very lightweight. In addition to allowing me to spend money on other things, this allows me to place ballast (the seat is required to weigh 25lb) in a position which gains me a weight distribution advantage (e.g. underneath the seat). Tillett seats are not allowed in any kind of "reasonable" SCCA class because the seating surface is not fully upholstered, and I'm afraid a Corbeau or factory Recaro won't change the position much. Besides, if I can afford a Tillett, I can afford a much more comfortable Bride Lowmax seat.
For me, half the fun is building the car (at least the first time).

speed7

@Federighi Yeah it's weird.. with what I call my "fancy seat project".. my source for parts is actually 425 Motorsports aka Planted Technology. When I did my first attempt at my race car install I used their planted bracket, sparco seats and sliders. And when you bolted all of that up it raised the seating position an inch or two. With my "fancy seat" install. I attempted to use Recaro sliders from Recaro Japan for the Rx8 and a Recaro seat, again from 425.. That also raised the seating position about an inch. The problem is the oem seats have the sliders built into them, which is great, but that's how constrained the cabin is with the oem seat installs. The only way to combat certain seat and get them lower is to rip out the oem mounting points and design your own. This doesn't do well for a "PNP" setup. It is what I didn't want to do with my fancy seat install. However if you have a set of sliders that allow you to connect side mounts then a traditional bucket seat from any company would allow you to lower the seating position. That was what I unfortunately discovered too late when it came to my race car. Also other brands might also make lower seating positions with rail kits.. Bride Low Max comes to mind, which are the seats I think you're running.

@TPNxl So I'm still waiting to hear from the person who did their install.. however I think this is what bracket they used. https://bride-jp.com/en/seatrail/lf/ You can see that the area between the sliders is open which should allow you to get a fairly low seating position. For when I attempted to use a planted bracket, the bucket portion of the lower seat was hitting the planted bracket, limiting the height adjustment available. I was using a Sparco evo seat.

Update:
I can add to this in more detail with pictures later, unfortunately I'm on my work pc atm.. and all of the pictures I need are on my home system. WFH and pandemic makes it so switching between the two takes time. So I tend to only do it "off hours".

Update 2:
@TPNxl The bracket they are using is from Corbau. https://corbeau.com/mazda-rx-8-03-11-seat-brackets/. And the seat they are using is the Sparco Sprint seat. They said you have to drill 2 holes to mount the slider and some messing with the bracket itself. But the car is untouched.

TPNxl

@speed7 I knew about the Corbeau brackets but I've also heard that some people trying to order them have had issues with receiving them on time; I also didn't want to drill holes if I can avoid it.

Something that has recently come to my attention is that Kirkey seats can be so lightweight is because they are designed to be used with a back brace and roll cage (when I went to Summit Racing today I was able to pick up their 55 series 20" width with 3 fingers). I do not want to use either of those at this point in my career, so I guess it's time to look for a seat that can stand up on its own to a crash. I'm looking currently at the OMP TRS-E XL seat and its associated side mount brackets because they have an FIA certification and are relatively inexpensive as well.

I do not want to purchase anything that's a Japanese import unless it's already in stock at a US-based dealer, simply because my next event is in a month and a week and I do not want to be dealing with getting a bracket the week before the event again. Also, I am afraid that my seat may still hit the bracket because I tend to sit close to the steering wheel (relatively speaking).

speed7

@TPNxl Ahh well I get where you're coming from. Side note, here is a bit of advice I have for when it comes to track days. If the car isn't ready a month prior to a track day.. especially if there are modifications / parts to deal with. You're not going. You need to prepare waaaaaaay further in advance. Too many times have I seen people rush rush rush... and there is no point. For an example.. I'm contemplating doing a track day in October. And I'm already mentally getting what I need organized now. And within the next month or so will wrap up my pre-work and commit to the weekend. Only thing I do the weeks prior is change the oil.

RE the seat brackets: The drilling of holes I mentioned before was in the bracket itself, not the car. I agree that a complete plug and play option would be great.. but sadly when it comes to installing a seat in this car.. that is going to be very rare. I've not personally used any OMP hardware, but I'm sure it's fine. If you're worried about safety you probably should be looking at OEM seats with air bags. And going with a full face helmet, not an open face design like you mentioned. I've been talking with Arai about their helmets since I have a space issue as well... and I suspect their helmets are a bit smaller in design. Specially the GP-5W. https://www.araiamericas.com/gp-5w-variation. Just something else to kick around as you navigate your track day setup.

speed7

@TPNxl It's a shame that the OEM recaro seats wouldn't work for you. Both myself and @Federighi have a setup for sale. His are nice.. mine are not so nice. But they are amazing OEM seats, with airbags, and hold you in really well for a track day.

Loki

iTrader: (1)

Regarding the seating position, it's a thing. The way you sit and grip the steering wheel for racing us usually different from how you sit normally. If you're used to sitting close, that's a start but see om YouTube about proper sitting position and see where that puts your head. The seat pan mod you found made a sufficient difference for me.

I wouldn't change seats without having a proper 5 pt harness. You're removing a big part of what keeps you safe in a crash and need to compensate. Best thing to do is do 1 track day with what you have before you make modifications. Talk to people, sit in their cars, get your instructors feedback.

TPNxl

@speed7 What I am worried about with the OEM Recaros is that the adjustment equipment and stock brackets will add too much height... and I'll be back to square one, only $500 lighter.

The way I am dealing with my track events is... it would be nice to go to XXX track event in a month, but I'm not going to pay for rush shipping or make impulse decisions if it might not be possible. You can register for SCCA events pretty close to the actual date they occur so it's pretty easy to decide whether or not to go the week before. (I have about a month and a half between my next possible event.)

@Loki I would go to a track event with the stock seat, but I could barely endure 10 minutes of local street driving with my helmet on because of how I had to bend my neck... I cannot imagine what it would be like at double that speed and cornering for 30 minutes at a time. This might be something dangerous to say, but given that I'm mostly going to be doing Novice time-trials with passing only at point-bys and autoX events, I'd be willing to take a compromise on an FIA-certified seat with stock belts until I decide I want or need a roll-cage.

speed7

@TPNxl Sending you a PM.

TeamRX8

iTrader: (25)

i’m 5-9 and have a ton of roof clearance in a base S1 with the Kirkey Intermediate road race seats (formerly 47 series, now 65 series) adapted to modified OE seat rails. I more or less stripped everything off the OE slider rails and tig welded some tabs on the sides of them that bolt through the sides of the seat. It’s even maybe too low for me now that I extended to a rearward steering wheel position. Am considering adding a foam pad if I don’t swap to the Tillet B1. Those are currently about $2150 each shipped from the UK with a long lead-time plus getting custom full surface coverings made to meet the rule allowance.

I also had to fab and attach a pull-arm across between the slider-adjuster tabs in the front to get that to fit & work for seat positioning. I don’t really have any more specifics than that, but anyone who can fabricate and has the equipment should be able to figure it out. Could even be a little lower. Had to tweak the outboard shoulder wing a slight amount inward, but it seemed way easier than other race seat installs where they cut out the rail across the floor under the seat area and such as you’ll find in the race forum area threads. Mine clears that area on the floor no problem.

They’re a bit of a pain to climb in and out of with the high sides and deep seating position though. A removable steering wheel helps some.
.

BluTyger

As an aside, what region are you registered for SCCA Time Trials? I just started with Rocky Mountain Time Trials in the Colorado region SCCA, and would love to talk shop and see what you have setup. Monkey see, monkey do kind of thing.