May 31, 1998
By: Richard Carlson

Although I love my Z, I've always been disappointed with the seats and the lack of support. I have the "Regular" seats, but I've found the same to be true of the "Sports" seats as well. I was reading a post from Jim Harriger who was similarly disappointed with the seats in his ///M. He said he had looked at the seats and found that the fronts are held on with two nuts. He planned on taking off the nuts, replacing them with rod-couplers and bolts. Sounded like a good way to get some support into the seat, but, as I found out, there are a bunch of gotchas!

Previewing the Project

I checked under my seats to make sure they were attached in the same way as Jim's. He has an ///M, while I have a 2.8. Sure enough - two nuts in the front, two bolts in the back. So far, so good. I took off the bolts and put some 1 inch supports under the front seat just to see how it would feel - I liked it! It made the seat feel like it was cradling you. Putting the seats back to the standard setup made it feel flat and unsupportive.

Obtaining the Materials

I paid a visit to the local Home Store. I found 5/8^th inch rod couplers which looked like the right size. I tried to screw them on - no go! I checked with the local hardware store who confirmed my worst fears - the nuts were not 5/8ths, they were metric 8mm. The problem is that rod couplers are pretty easy to find, but metric rod couplers are a specialty. I emailed Jim who confirmed - he had found a local source for the 8mm/1.25 rod couplers. About $2.50 each.

I looked in my Yellow Pages under Fasteners, but the first few places I called didn't carry metric. The third place suggested I look under "Metric" instead. Bingo! They had them, and for only $1.50! (Sorry Jim - looks like I got a better deal).

I got 3 couplers and two bolts. The couplers look like very long nuts, 24 mm in length (about an inch long). I got the third coupler because I had a feeling I might end up cutting them down to size (I was right) and wanted to have an extra one in case I messed up The nuts are about 1/2 inch long (about 12 mm long). I also got a couple of washers to provide backing and support at various places.

Update: On the net, call Maryland Metric 800-638-1830 (http://mdmetric.com/prgde3b.htm). They have a $10 min order the couplers and bolts and the washers for both sides and you'll probably just about hit $10.

The Procedure

The procedure is quite simple. If you want to use Jim's method, all you really need is a socket set. I also used a Dremmel tool and a saw for some wood-work. Jim indicated that he simply moved the seat forward, unscrewed the rear bolts, moved the seat back and removed the front nuts.

He then put the rod couplers onto the screws which protrude from the floor, fastened the front with the washers and bolts and re-fastened the backs.

Note - it's easier to put everything in place loose, then tighten the back, then the front.

I tried this procedure first. It worked fine. When I took the car out on the road you could immediately tell the difference --- I could feel my buns being grabbed by the seat! I never felt this in a Z! It was great - for a few minutes. After that, the sensation got a bit too intense. I was afraid of this - Jim is 5'10". I'm 6'1". He probably sits with the seat higher up than I do, so the sensation is not as great. The 1" raise in height was just a little too much for my tastes.

The Alternate Procedure

The Alternate Procedure is a bit more involved. It's designed to give the seat a bit more support and to remove about 1/4 inch of extra height:

• First I used the Dremel Tool to lop about 1/4 inch off the rod coupler. Be careful - you don't want to remove too much or you won't have enough coupler left to attach the bolts.
• I then cut several stabilizer units from a piece of wood. I painted these flat black and used them to surround the shorter rod couplers. I also hollowed out a little bit of the top to make a "cup" to mate to the underside of the rails of the seat-foot where there is an indentation (it's hard to explain, just reach under there are feel around, you'll see what I mean)
• I re-installed the shortened rod-couplers and surrounded them with the wooden stabilizer units.
• Tightened up the rear nuts
• Tightened up the front nuts

And I was ready to go. The next test drive was a dream! The 3/4 inches made an incredible difference to the feel of the seats. I'm now quite happy with them.