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I just finished installing Miata seats in my TR8. I had a couple of reasons to be interested in this, the main one being an effort to preserve the original velour style seats that were used in 81. No reproductions are available, and in the last year the wear has accelerated. Also, burlap and foam are rapidly breaking down (the diaphragms are fine, however), and if I tried to replace those, I'm not sure the original covers would survive.
So I picked up a pair of 1990 Miata seats at a local wrecking yard that specializes in Mazdas. My main goal was to not make any permanent changes to my Wedge, and secondary goal was to minimize changes to the Miata seats, in case it didn't work out. I succeeded in the first, and only made the same changes to the Miata seats that are done when mounting them in a TR6 or MGB.
My initial attempt was to mount the Wedge track to the Miata seat. One advantage of this was that the Wedge track is also the mount for the seat belts. However, because of the way the Wedge adjustment handle works, it would need to be mounted at least an inch and a half away from the seat pan. So that was out.
My next attempt was two simple plates to mount to the Wedge using the original mounting holes, and with studs for the Miata seats. I got those all layed out for the passenger side, using 2" x 18", 3/16" steel bar stock. This seemed to work well, and I had the seat mounted on the same centerline as the Wedge seat.
Then I went to replicate this for the driver's side seat, and found that while the tracks on the Miata passenger seat where equidistant from the center, the right hand side track on the driver's seat was about 3/4" in board. So I took some more careful measurements, and found that the Wedge seats are about 1" inboard (using the steering wheel as a reference). And since the Miata seats are narrower, there is room to make them more in line.
Because I originally had the Miata tracks just inside the original mounting bolts (it was a very close fit), I had to move them over to the other side, but that was just about the right amount (1"). So that meant the right hand side bracket on the passenger side could remain at 2" wide (and I was able to flip over one of brackets I already made), and the left hand bracket became 3" wide. One the driver's side, because of the track offset, the right hand side is 4" wide (and again, I was able to flip and reuse one of the 2" brackets for the left side).
To mount the seat belts, I made some simple L-brackets that attach to the seats between the seat pan and rails.
Compared to a sagging stock seat, seating my seating position is about 2" higher. It actually feels a little more comfortable there, and getting in and out is much easier. The only downside is that seeing traffic signals is a bit more of a pain.
Eventually I plan to recover the seats with something that matches the interior better, but I'm still working on that. I also plan to add headrest speakers.
So I picked up a pair of 1990 Miata seats at a local wrecking yard that specializes in Mazdas. My main goal was to not make any permanent changes to my Wedge, and secondary goal was to minimize changes to the Miata seats, in case it didn't work out. I succeeded in the first, and only made the same changes to the Miata seats that are done when mounting them in a TR6 or MGB.
My initial attempt was to mount the Wedge track to the Miata seat. One advantage of this was that the Wedge track is also the mount for the seat belts. However, because of the way the Wedge adjustment handle works, it would need to be mounted at least an inch and a half away from the seat pan. So that was out.
My next attempt was two simple plates to mount to the Wedge using the original mounting holes, and with studs for the Miata seats. I got those all layed out for the passenger side, using 2" x 18", 3/16" steel bar stock. This seemed to work well, and I had the seat mounted on the same centerline as the Wedge seat.
Then I went to replicate this for the driver's side seat, and found that while the tracks on the Miata passenger seat where equidistant from the center, the right hand side track on the driver's seat was about 3/4" in board. So I took some more careful measurements, and found that the Wedge seats are about 1" inboard (using the steering wheel as a reference). And since the Miata seats are narrower, there is room to make them more in line.
Because I originally had the Miata tracks just inside the original mounting bolts (it was a very close fit), I had to move them over to the other side, but that was just about the right amount (1"). So that meant the right hand side bracket on the passenger side could remain at 2" wide (and I was able to flip over one of brackets I already made), and the left hand bracket became 3" wide. One the driver's side, because of the track offset, the right hand side is 4" wide (and again, I was able to flip and reuse one of the 2" brackets for the left side).
To mount the seat belts, I made some simple L-brackets that attach to the seats between the seat pan and rails.
Compared to a sagging stock seat, seating my seating position is about 2" higher. It actually feels a little more comfortable there, and getting in and out is much easier. The only downside is that seeing traffic signals is a bit more of a pain.
Eventually I plan to recover the seats with something that matches the interior better, but I'm still working on that. I also plan to add headrest speakers.
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