Racing seats for big guys or How to measure for seats?

Especially after sliding around in the rain today, I'm noticing my 23 year old stock miata seats aren't really holding me as well as I'd like, and aren't nearly as comfortable as they should be. I also learned if I put my helmet on inside the car with the top up, it fits, but I can't turn my head. While a foamectomy would help with the head clearance, I'm thinking a race seat would be better for side to side support. Not that it isn't a blast running with the top down in the rain.

Where should I measure me, or the seats in the car, or new seats to figure out what to buy?

I'm 5'10, 300lbs and trying to drop. 44" waist, 30" inseam. I do have "short" legs I guess. I noticed on S13 boards Nigesa rails, but I've never seen them recommended in a miata. I don't care if I wind up just bolting a seat to the floor, although I haven't sat like that and don't know how the petals feel in that position.

Any recommendations for seats or rails? Or maybe a big and tall store of the racing world I haven't found yet? I'm not in a big big hurry, I've got a bunch more projects in line first, but if I can start looking and watching for sales I might find a good deal.

Hell, are there any stores around Pittsburgh where you could go sit in a bunch of different seats like at a furniture store?

Sit down and measure to the outside of your upper legs.

This is the common race seat measurement (width).

All other measurements vary with seat design.

Many of the locost guys have cushions that velcro into the tub.

The biggest seats out there are Recaro SPG XL and Racetech 4009W's. Try and find a shop that carries them so you can try em out...

docwyte wrote: The biggest seats out there are Recaro SPG XL and Racetech 4009W's. Try and find a shop that carries them so you can try em out...

For that money I could buy a bigger car to run. Wow. But thanks, I can keep an eye out at least.

I have found the measurements don't always tell the whole story. The Corbeau FX1 is economical and fat guy friendly. Its what we run in the chumpcar for drivers that range from 44 to 32 waists. They also make a wide but it may not fit in a Miata. I have a used wide FX1 I would sell if you are interested in making a trip to the other side of the state.

OMP TRS-E Plus

I'm 6'4" and about 320 (46 waist) and I fit. They also don't cost what the Racetech or Recaro cost. I found a used one for $180 USD.

logdog wrote: I have found the measurements don't always tell the whole story. The Corbeau FX1 is economical and fat guy friendly. Its what we run in the chumpcar for drivers that range from 44 to 32 waists. They also make a wide but it may not fit in a Miata. I have a used wide FX1 I would sell if you are interested in making a trip to the other side of the state.

If I can find the time to make the trip, I may have to take you up on that. I'm curious to see the mirror name city. My weekends are booked up for the next couple weeks, kids bday party then 2 weekends of autocross. but I could see a late June road trip being possible. 5ish hours isn't too bad though.

I will say that Sparco Evo 2 Plus seats don't fit in a Miata with mild sledgehammering. I might have made them work with more hammertime, but I'd rather just go with the UltraShield Rallysport 17 in. Cheap and effective. Track Dog Racing sells an "expensive" floor mount for it that makes it very easy-button.

For a Miata, your best bet is probably going to be an Ultrashield/Kirkey. It's a delicate balance of finding a seat that you fit in and also fits in the car. That second part is quite a bit harder in a Miata than in many others.

The Corbeau FX1 Pro will fit in a Miata, but the shoulder "wings" will hit the door panel unless you have the seat way up high. We've had pretty good luck with the Sparco Sprint.

A good foamectomy can definitely increase lateral support. Don't do the over-simplified cutting you see online. My recommendation is to skin the seat, then reassemble it. Start sitting and trimming and sitting and trimming. If you take some foam out of the back, you'll gain some good torso support. The base will also develop more support if you do it right.

Here's one shot of a seat I did a few years ago. I did take a bit out of the bottom of the base as well.

Here's another.

when I was selling seats (Sparco, and Corbeau) the only thing we felt confident in fitting the Miata, was the Corbeau A4...

As to sliders... if you go with bottom mount sliders... ONLY use double locking.... single locking can be dangerous.

If you are buying new seats, and want a foam-ectomy, Corbeau does offer this service, in essence they cut out 5/8" of the bottom pad (or use too... back in the mid 2000's)

Watching with interest. I'm about your size.

Ugh, not a fan of the A4 here. I can confirm the Sparco Sprint will fit.

I took the bottom cushions out of my FX1 Pros and replaced the foam with Backsaver foam from Pegasus racing (blue Confor foam). Dropped me down by a significant amount and changed the seat from 30 minute comfort to 13+ hour comfort.

Watching as well. Im roughly those dimensions, and i have a helluva time fitting in a miata.

Regular SPGs will require some floor hammering and will hit the door. I wouldn't even want to know how badly an SPG XL would fit.

NRG makes a larger seat. My 6'2" 250lbs fit in them with no issues.

After having the seat out of my Miata I cannot imagine it being easy to have sliders or substantial mounts in there at all AND fit a seat in for a tall/wide person. Honestly I fit in just fine without any seat at all...

Keith, I appreciate the pictures and foam tips. I may get into that tomorrow if I don't make it to home depot for the stuff to get my doors ready for paint.

If I can get away with it, I don't think I'll be using any rails, just mount the seat and tell the short guys they can't drive it anymore at auto-x.

This might turn into a really expensive road trip, there's a miata graveyard of sorts kinda on the way, that advertises all 3 flavors of torsen in a full swap kit for 700 or less. I wonder if they'll take my full VLSD as partial trade...

In reply to revrico:

Follow the other suggestions for eliminating seats and creating a list of possible seats, but dont buy anything without sitting in it first (unless of course returning it is easy and cheap).

The earlier Miata was width limited in the interior (length and height too but that is unrelated to choosing a seat) so be sure the outline of the seat fits between the door (or cage side bars) and tunnel with enough room to attach the lap belts to the rocker/tunnel. I have seen a couple configurations where the person setting up the car wanted to use eyebolts for the belts but lacked enough space between the seat and tunnel/rocker to install them. Note that the latest lap belt installation instructions say the lap belts should lead to the seat openings at a 60-80 degree angle from the horizontal (see:Schroth Installation instructions) which generally means the anchors cannot be placed aft of the seat side profile.

I know of one fairly tall racer that modified the floor some and made custom seat mounts (not always permitted by sanctioning body rules for FIA seats) in order to install an FIA race seat in a lower position (he is tall and after his work he is able to sit in his caged Miata (the cage fits under the convertible top) and his helmet is below the upper bars. I should be able to get you his contact info if you want to learn more from him.

When measuring your butt/thighs for a seat, sit between two cinder blocks. Put the cinder blocks against your legs and measure the width between the cinder blocks.

That was how it was described to me to measure. It worked well! Our Ultrashield Rallysport seat is super comfortable! (Especially after some extra foam in and uncomfortable spots).

revrico wrote:

logdog wrote: I have found the measurements don't always tell the whole story. The Corbeau FX1 is economical and fat guy friendly. Its what we run in the chumpcar for drivers that range from 44 to 32 waists. They also make a wide but it may not fit in a Miata. I have a used wide FX1 I would sell if you are interested in making a trip to the other side of the state.

If I can find the time to make the trip, I may have to take you up on that. I'm curious to see the mirror name city. My weekends are booked up for the next couple weeks, kids bday party then 2 weekends of autocross. but I could see a late June road trip being possible. 5ish hours isn't too bad though.

Good news. I found the seat.

Bad News. Somewhere during the move from Michigan, something decided to chew on it in the butt zone.

Good news. The damage cant be seen if the cushion is in it.

Bad news. I seemed to have lost the cushion during the move. Not sure if its here, back in Michigan, or at a truck stop in Canada.

Good news. Depending on your torso height, you may not have needed the cushion. (I take them out due to my Fred Flinstone build)

Not sure if you are still interested in a slightly damaged fat boy seat but here is a picture.

Is it worth 100 bucks to you?

In reply to logdog:

Yea it will be once I get these other projects out of the way in a couple weeks. I'm looking at those pads/cushions keith recommended, if I understand it right, that will replace the chewed part. Not a big deal to me how it looks, as long as it'll hold me.

I'm going to try to be really slick and stop at Mike's miata parts in middletown either on the way out or back and swap my vlsd for a torsen too. Unless he just has an outdated price list online.

Once I get the paint done, I'll have time to come out, unless you're coming to solo nationals in July at Pitt race.

You'll still want some sort of cover for the Confor foam. I know that Corbeau sells replacement bottom cushions.

I just realized I've got a Corbeau Forza that's got welded-on Miata seat rails. No bottom cushion (there's a theme here) but let me know if anyone's interested. Guaranteed to fit in a Miata, obviously. It's blue because that's sportier.

In reply to revrico:

No solo nationals but we will be racing the Chump race at Watkins Glen this weekend (shameless self promotion! )

I will hold it for you. It can hang out on top of my toolbox until you can make it out east.

docwyte wrote: The biggest seats out there are Recaro SPG XL and Racetech 4009W's. Try and find a shop that carries them so you can try em out...

AND MAKE SURE THEY FIT IN A MIATA.

I'm almost the same size as the OP - maybe 25 lbs lighter, but same dimensions. I have Corbeau FX1s in my NA, and they just fit. There is an FX1Wide but I think it literally would not fit in a Miata with side windows and a top.

I fit in the FX1s comfortably enough. I would be better off in the Wide, but as I said, I don't think it would go in the car with the doors closed.