Seeking passenger seat advice
 

I'm getting ready to pull the trigger on competition seats and harnesses. For myself, I plan on getting the Sparco Circuit. This seat is made for small-ish guys, so just buying a second one for the passenger side won't be an option. My main constraint is I want a FIA seat to keep the safety specs the same for driver and passenger, and I am also leaning toward a halo seat for the passenger side as well.

I am trying to determine what seat to accommodate a wide range of instructors and passengers. Will the Circuit II fit the bill for most passengers? I am looking to keep each seat under $1k, even though the damn $1400 Racetech 4009 fits me like it was custom molded :vash:

I'm not sold on Sparco seats for either side, but it would be nice to have both seats of the same brand if possible, and I think the Circuit will fit me nicely.

Questions/comments/suggestions are greatly appreciated.

I wouldn't bother with a halo (new or used) for the passenger seat. My research is a bit out of date, but the Momo Start used to be the widest FIA fiberglass seat available and will accommodate people with ~34" waists with no real issue. Spending money on an XL passenger seat seems like throwing money into the fireplace.

Have you personally used or sat in a Start in a miata? I guess as long as it will sit low enough for a tall-ish guy to pass the broomstick test it's alright.

Thanks for the input.

Instructors, what do you think?

I love that you are concerned about the passenger - many do not think of it and try to go cheap.

I owned a Momo Start several years ago. I do not remember it being overly wide. If you mount it on seat rail sliders, there not be a lot of headroom, as you'll likely need an adapter bracket between the seat and slider unless you fabricate something. That's the problem with the composite seats I've sat in.

I vaguely remember a Sparco seat with removable bottom cushion in a student's car. Not the most comfortable thing (without the cushion), but lots of headroom and I could certainly deal with it for 20-30 minute sessions. I'm neither tall nor overly heavy.

If you are fix-mounting the seats, without sliders, then you'll definitely have more headroom and less issues.

A big 16-17" Ultrashield seat will fit just about anyone with headroom to spare.

As Chief Instructor, one of my responsibilities is paring students with instructors, and a good portion of that has to do with putting instructors into cars that they will fit!

Yes to both.

The Start isn't super duper wide, but it is/was the widest seat in the hips that wasn't a Kirkey. Racetech, Sparco, and Recaro's entry level seats were all narrower than the Momo Start.

I have a Momo Start in my car on factory sliders. My dad has a 38" waist and fits barely, my 34" friend states he would have trouble with long drives but a track run would be no issue. The start worked for me on a 10hr drive from MN to MI and back.

Echoing this, I've had a few instructors with different organizations switch up the pairing when they didn't fit. You don't necessarily need to fit the 90th percentile of instructor size by buying an XL seat.

I have a Tillett seat on the passenger side (they make a nice FIA model), and it is LOW, even on a welded adapter side-mount that sits on the "bumps." It would easily fit a much taller person than my Sparco Ergo driver's seat. No halo though.

I never had a problem getting an instructor in my car with Momo Starts on both sides. Generally the guys too big for a Start are too tall to go in a Miata anyway.

I too appreciate the fact that you are putting some thoughts into the passengers seating. As an instructor and a big guy. Go with a 17in Ultrasheild or Kirkey seat. Light, cheap, and will fit most everybody including my wide ass.

I have had to change students several times due to not fitting.

As someone who has sat in starts in a miata I have always felt like my back was going to break. Something about the seat shape and layback angle is extremely uncomfortable at 6'4". Also the shoulder belt openings are too low for tall people. It is a moot point unless you go out of your way to mount the seat specifically for tall people (remove mounting humps, mount with extra layback angle).

The cobra suzuka GT (its the wide version) should just barely fit in the passenger area and is about as wide as the start. You might need to clearance your door card/crash pad or trim the shoulder wing. It is also more expensive than the momo start. I had one mocked up in my passenger seat area until my doors took up some space.

For reference, here is a pic of the underside I took for someone before I sold it:
https://i.imgur.com/LdK0wJQ.jpg

The other nice thing about this seat for tall people is that the butt area is reasonably round so as it you lay the seat back you aren't cantilevering the occupant off of the floor pan.

Funny you mention it. I was helmet shopping yesterday (hooray, SA2015), and sat in a Cobra Suzuka and Suzuka GT (wider version of Suzuka). Not sure if either would fit in a Miata, but the removable cushion makes them pretty flexible for street and track-day use (for getting under the rollbar).

An aluminum seat will be cheaper and easier to fit, but also requires a properly installed and angled back brace. The brace is not always easy to do with off-the-shelf rollbars. Depends if they have a harness bar, and its location.

If you can, I'd suggest visiting a shop that has seats on display.

Thanks for the input guys!

To be clear, I'm not trying to fit the largest instructors in the car, I just don't want to pick a seat that will be too small for every other instructor.

The new Sparco Evo is supposed to be a little bigger than previous models, so I'm considering it. The Start sounds like it might be the way to go, anyone else think the Start is uncomfortable besides Asm?

There's a racing shop in Cresson that has some seats, that's where I sat in the Racetech 4009 and I've regretted it since. Can't afford that seat.

I'm not going to do an aluminum seat, mostly because no FIA approval, and I don't want to jack with back-bracing it correctly, and the 2 shops I have spoken to both quoted me 300 a side to properly brace an aluminum seat to my rollbar. That makes the cost "savings" pretty much moot.

The Tillett seats look pretty nice and seem very light for a FIA seat. Expensive though, at least on their website.

asmasm is super tall and doesn't really count.

Also, you can afford a Racetech 4009 for yourself now. $1000 per seat is $2000 total; 4009 = $1400, Start = $400, Side mounts = $100 per seat

I'm with asmasm. I had a student with a Start and it was pretty uncomfortable and the belt holes were way too low for me. The Momo Supercup XL would be a much better choice. I have a regular width Supercup right now and it's pretty comfy with really tall shoulder belt holes. I think I paid $629 shipped for this one. I think the XL is the same price and it should fit damn near anyone.

Disclaimer: I have no clue what seats fit miatas with interiors.

Dunning - Haha yeah I've already done that exact same justification math.

Just found the Sparco Ergo. Looks like a big, tall seat, but I'm liking the removable halo aspect. Thinking about this for my driver side unless it is too big for me. I was just going to get a halo seat and learn to deal with it on the street, but the Ergo may be a great convenience. Anyone run an Ergo?

I'm going to pull the stock seat belts and install harnesses at the same time as the seats. I need to dig and find info for properly securing the lap and sub belts to the chassis.

It wouldn't be a bad idea to make a comprehensive how-to on making those attachments if I can't find anything, unless the way to do it requires welding, then I'll just let a racing shop do the work.

I also need to dig up some info on properly mounting the seats. I'm starting to realize I have a bunch of research to do.

I'm going to try and make the seats easily removable, still thinking about how to accomplish that. Ideally, I would like to remove the seats by simply jacking up the car and removing 4-6 bolts per seat, and the whole seat and mounts would come out as a unit. Maybe I should start a build thread...although it would be pretty damn boring. Decisions...

I have a medium Ergo in my car. My car has the rear seat mount "humps" cut out, which gives the seat some extra recline and makes it very comfortable. I am 5'10, but a 6' person can have the helmet below the main hoop with the butt pad in.

Interior shot:

https://www.miataturbo.net/attachmen...ine=1461459752

^ You've got my attention. Did you ever weigh the seat? Did you use off the shelf brackets or custom?

Did not weigh it myself, but Sparco says 16.5lbs sans brackets.

I had TC Design make a bracket that works with the rear "hump" delete, but it also worked on standard side mounts bolted to Miata adapter bases. A custom bracket with deleted rear humps is definitely much better for getting the seat low.

I don't know about these other seats but I don't believe any of the Racetechs fit in Mx5's.

I have a new Racetech RT1000 i got cheap (ex demo) for my M3 but a quick measurement and the shoulders are WAY to wide. 10 cm's more than the momo's in my mx5.

From my casual inspection of the Racetech size chart that seemed to me like none of the others would fit either...

Would welcome this to be wrong as Racetech are made here so one of the few, quality seats we can get at reasonable price....