In the quest for more helmet clearance for track days, I have gone to an aftermarket seat. The seat I chose was the Momo Start 2007. This is one of the least expensive FIA homologated seats I could find (the only less expensive was a Sparco sprint seat). The Start 2007 is a side-mount seat (side-mount seats generally can be mounted lower than bottom-mount seats). The FIA homologation means that the seat can be safely mounted without needing to be attached to a roll bar (a roll bar generally prevents use of the back seat). The Momo seat is quite tight for my behind. This seat is recommended for up to a 36" waist -- I'm a 33" and am wedging myself down into the back of it. I don't know how a 36" person would possibly fit (unless those extra 3" were in the front!).

I bought a "super low position seat mount" from MemoryFab (http://www.memoryfab.com/products/detail_accessories_3/). They don't make the bracket -- they are just an importer. The bracket actually came from http://www.japanseatrail.jp/ (they show some sample seats with their bracket in RX-8s at http://www.lastrada.jp/cont/seat_rail/type/photo/mazda/rx8-se8.html). I got a seat mount with dual-locking sliders on it. MemoryFab is slow as a Smart ForTwo, so leave plenty of time to get your stuff (mine took over 2 months after ordering).

I routed the seat belt the same way as Derex'8 did in http://www.rx8club.com/showthread.php?t=128244.

Some pictures are below of the installation. The only tight spots are the shoulder wings on the seat interfere with the rear door handle if the seat is back too far (which isn't a problem for me in a comfortable driving position); and the seat belt receptacle is a bit hard to get at. I plan to go to Mazda and order another receptacle (in addition to the one that came with the car), so I can leave one permanently mounted to the new seat. I may also drill a new mounting hole a bit further up the strap on the receptacle to allow better access to the release button.

I believe I gained about 1-2" doing this, which actually allows me to sit in a reasonable driving position now with a helmet. My helmet still hits the roof where it slopes toward the door, so I would like to find another inch if I could.

The whole process took about 2 hours. Future removal/installation will probably only take 20 minutes now that the seat and rail are assembled.

Weight: the Momo Start 2007 weighs 20.0#, and the MemoryFab bracket weighs 9.5#. The factory seat with the seat rail bracket is 39.0#. So I have also removed about 10# of weight from the car.

More pictures. All the brackets and hardware shown came with the seat rail kit from MemoryFab.

Directions that came with the seat rail (original Japanese, and translated to English)

Nice,
future removal and installation is considered with the reinstall of the stock seat? Police officers here are a pain so hanging around on race seats is not the best option.
Thank you

Removal and installation is pretty straight forward. There are 4 bolts holding the seat down to the floor of the car, and you need to remove one bolt from the seatbelt bar under the door to fish the belt back out of the seat. Oh, and the electrical connectors under the seat. After that, just lift one seat out and put the other in.

I don't think it is a great idea to drive around with a race seat in all the time, either. It's comfortable, but certainly not as comfortable as the stock seat. You also lose the air bag protection from the stock seat, and there is the question of what the police will think of it if I get pulled over (knock on wood that doesn't happen!).

The seat I got is black, with just a small amount of yellow from the Momo logo at the top. This matches the interior of my car (black/gray), and doesn't stick out as much as a bright blue or bright red seat would.

I have an open track day in mid-October I'm going to. I'm planning to use the next few weeks to make sure the seat is where I want it, and tweak the seatbelt placement and height, then pull it back out after the OTD.

Got you :)

Went up to WHRRI for an OTD last weekend. You can read about it in Doug Guthrie's blog at the Detroit News:

DetroitNews Motorsports Blog (http://info.detnews.com/redesign/blogs/racingblog/index.cfm?blogid=374)

To put it mildly, the seat was awesome. I don't think I realized how much support it provided until I took it back out earlier this week and put the stock seat back in. Now I feel like I'm riding in a SUV, with a cushy seat and a "high" view of the road.

I made a few modifications since the original posting to get the seat a bit lower. In the end, I added about 2" total head room compared to stock, which allowed me to sit up in a reasonable position with helmet.

The changes I made from the original posting include:

1) Pushing the seat belt receptacle up through the seat. I had hoped I could run the buckle out through the right side of the seat and into the receptacle between the seat and the center tunnel, but there just isn't enough room, and the buckle required some contortions to get it through the slot in the side of the seat. I made an extension for the receptacle to allow it to come up through the slot in the side of the seat. Much easier to put on and remove the seat belt now.

2) If you look back at the original pictures, the seat mounting frame was a 4-sided piece. I ended up cutting the cross-members out, which allowed the seat to move down about another 1/2". The picture of the seat upside down shows the modified bracket.

Things I would do different next time:

1) Buy the non-adjustable seat bracket. It will sit you lower, it costs less and you don't have to wait 8 weeks for delivery.

2) Get a seat with an adjustable lumbar. The Momo has a solid cover stretching over the whole thing. Some of the other seats I looked at had removable pad sections in the back, which allow for lumbar adjustment. Not this seat. Probably part of the big difference in cost between the Momo and some of the others.