Modifying Stock Seats

OK...so I really like my new BRZ, except for the seats. For some people, I'm sure they are great, but they leave me with a hurting back after only a few miles. It's to the point I hate getting in the car. Since I like almost everything else, I'm considering modifying the seat considerably.

My initial thought is to go ahead and go to an upholsterer and have it done correctly. I want it to look stock, but have maybe totally different foam and sculpted the way I want it. Has anyone done this here before, and if so, was it worth the effort?

I've done the seat mod on several Miatas, but this going to have to go far beyond that to make it live-able for me day in and day out. It sucks getting old....

My Miata seat cushion has extra steel thigh supports welded to the frame, and all the foam is from an A2 VW GTI. The seat back is stock, I think. I may have thinned down the back insert, but I don't remember for sure.
Your seats will be more complex if you fiddle with the back. I'm assuming that the seat has an airbag. Your may find that the upholsterer isn't too keen on touching the back at all,especially the area where the bag blows out.

I might be ok just doing the bottom. It's designed to lay you back pretty far, and the bottom is like a bowl to hold you in place. Also, the head rest is non adjustable and leans in pretty far. If you put the seat more upright, it has you looking down. The foam is also hard as a rock. I think my old FIA race seat had more padding!

Right now I have the head rest turned around, but that's not an overall good solution, and it still does nothing for the bottom of the seat. If I were 25 again these would probably be great...

I used to work for one of the major OEM seating suppliers. Our comfort engineer told me that 80% of a seat's comfort is attributable to the cushion. Shape and support counts for more than the firmness,too.

I foam-ectomied a headrest to make room for a helmet, I removed a slice of foam that was maybe 0.75" at the thickest point. It almost looks factory, but the fabric is a bit loose on it now.

How tall are you? Do you have the seat bottom raised or lowered?

I'm old, 6'2" and 235 lbs. I'm pretty comfortable in my FRS. Raise the headrest if it is bothering you.

I'm only 5'9" and it's not that I'm not comfortable sans the neck and back issues, but the seat causes pain in those areas. I have disc issues in both. I've tried just about every position it has and it doesn't change the fact that it's a problem. By contrast, I had zero issues with the 370. It had nice seats that were infinitely adjustable.

I think it's the fact that is puts constant pressure on the lower disk due to the "bowl" you have to sit in on the bottom cushion and the rake of the seat back. The head rest simply comes in too much no matter what level you place it. There's no way to straighten the neck while sitting in the seat.

I hear you on the stock seats of the FR-S...I'm 6'2" and they could be better. I hate having to lean forward and look up just to be able to see the signal lights at an intersection, my eye level is nearly at the top of the side window in this car with the seat in the lowest position it can go. Forget about helmet fitment without really compromising the driving position. I've yet to have a stock seat that was done right from a pure ergonomic standpoint - Always have to go aftermarket and pay $$$$ for an ergonomic Recaro if you want a proper seat. I would have put in my Recaro Ergo seat if it weren't for the fact the seating position would be raised and I already really need it lowered 2"s to be at a more ideal driving height...

I know from the FT-86 Forum there is a local shop that has modded the stock FR-S seats to sit lower than stock and still retain a good part of the sliding range through a combination of seat bottom reduction and seat frame modification. Not sure what kind of ergonomic improvements were made though. For me the stock seat bottom is too short and puts too much pressure on my thighs for long trips along with just a tad tight in the shoulders - it's okay for daily driving/trips less than 1 hour.

Would you be able to fit a 370Z seat in your BRZ? That may be easier than modifying the stock seat.