2nd Gen suspension advice.
 

I am considering purchasing a 2nd gen T II and preparing it for B-Prepared SCCA auto-x. I have 4 years of experience in auto-x (4 regional championships) in BMWs, but do not know squat about RX7s.

For those who have raced or auto-xed 2nd gen...I would like some general info about the suspension and how to set up or pitfalls I probably do not know about.

I will modified the front stuts to coil overs with either Advance designs or Moton. I am more concerned about the rear. Anything I need to know about?

Thanks

Whatever inserts you go with just use the same out back. The front is where the problems are. If you can get it lowered where you want it without throwing in tons of bumpsteer and having zero shock travel you're in business. Out back make sure everything is up to snuff and expect to replace alot. There are spherical bearings for the trailing arms which I recommend. They'll hold the toe setting much better than urethane or delrin. The DTSS bushings have to go for certain. Make certain the small toe links on the inner front of the trailing arm and the lateral links are in top condition or replace them. Use a spherical bearing or delrin for the lower shock mount and hard mount the upper mount with another spherical bearing.

Don't go too low in the back or look for ways to clearance the front ball joint of the lateral links if you need to go real low. They will bottom to the floor pan long before you run out of travel at the wheel.

Going beyond the rear suspension, in my experience stick with the power steering rack for autocross. The manual rack which I use for my ITS car is too slow for the much tighter, slower corners of an autocross course. I've autocrossed both and prefer the quicker power rack hands down.

Based on running my ITS car in two or three autocrosses I'd guess a starting spring rate at 400lb front and near that at the rear. Something in the 350 range. I ran with a 1.125 front bar and no rear bar. I'd put the stock rear bar on as a start for an autocross exclusive car.

Just my thoughts.

Basicly, to be competetive you will need a full widebody like my/ steve o'blenes/25BP's cars. Typically all the trick AWR pieces(like an SCCA EP car), widebody, ~300+rwhp/ min weight. AD's will get the job done. Most popular tire size 23.5x12x16 hoosiers/goodyear/avon slicks. I'd start with a retired race car, already gutted. There are completed AWR subframes in the FS section(silly expensive though). It used to be you could get away with stock hybrid turbos, but to compete at your level, you willl need to go to a 60-1 turbo, and all the supporting equipment. You can call me at 707-696-2705 to discuss if you like. Good luck, Carl Byck.

BTW, if you search "widebody" here, and on Teamfc3s.org, you will get the idea. Probably about 20k to build a nationally competitive car, assuming you already have the driver ;).