Monza355

iTrader: (3)

I'm looking to do a good suspension swap or maybe an overall floor pan/chassis swap. I'd like to see some pics of the front and rear suspension as well as engine bay pics less the engine.

Thanks,

Bill

rotoober

iTrader: (8)

What year/model? FD, FC ? I can snap some pics. of my FD this weekend if need be.

Monza355

iTrader: (3)

FD prefered FC also has 95.5" wheelbase so that'll work too. Turbo's have the larger rear diff, right?

Thanks,

Bill

Project GatTagO

iTrader: (7)

Here is a picture of the FC rear suspension.

Andrew

Monza355

iTrader: (3)

Thats what I need. Is there only four bolts holding that in? Can you get some measurements for me? I need the wheel mounting flange to wheel mouting flange, distance between the calipers and the mounting pattern for the subframe. What size centersection is that one? R160 or R180?

Thanks in advance!!

gnx7

iTrader: (28)

The FD and Turbo 2 (FC) ring gears are 8" and are pretty beefy. n/a FC rear ends are only 7" ring gears.

There have been a number of automatic small block/nitrous FC's in the mid 9's with the stock Turbo 2 rear end and factory IRS. I believe that Hinson went a mid/low 9 second pass with a twin turbo LS1 and stock FD rear end with Kazz LSD and 300M axles.

Manual transmissions tend to do explosive things upon launch with either rear end. The FC LS1/T56 guys have broken stub axles and chewed teeth off of ring gears (4:10 only choice for T2 or deeper) when in the mid/low 11's. Some even in the 12's.

The FD rear end is offered in a 4:10 manual or 3:90 auto and the automatic ring gear is slightly stronger due to its number of teeth.... the stock Torsen LSD may be the cause of split iron cases (many instances). The housing itself has been known to crack when using the stock Torsen under even medium conditions or even a small amount of wheel hop. I believe the Torsen fails and the ring gear climbs the pinion gear ultimately making the case flex and fail.

Monza355

iTrader: (3)

I'm running a turbo 350 so I think the larger 8" ring gear in 3.90 ratio would be best. I'm running a stock 305 hp 98 LS1 so it should old up good. Now I just need the mounting diemensions...


Bill

su_maverick

iTrader: (9)

good luck, Id take pics of my FD but its too dark to get any good ones and I cant get enough distance for the camera.

Project GatTagO

iTrader: (7)

Here is a link to a complete 1988 RX7 service manual:

http://www.rx7city.com/88manual.htm

In the suspension section there are a ton of diagrams that might help you. You can also find specs on track width and such. I believe the rear track is 59.5 inches, same as a Fox body Mustang.

Andrew

su_maverick

iTrader: (9)

I know that with some custom half shafts you can fit a mustang cobra's 9" rear end into a FD so you might want to look into that for your rear since it is going to be much more durable than a FD's diff.

Project GatTagO

iTrader: (7)

The Mustang Cobras use an 8.8" diameter ring gear. These rear ends don't have much in common with the old 9" Ford units.

Andrew

Skele4door

iTrader: (1)

Here are a few pics of the 3rd generation rear subframe/suspension from my car. The only thing visibly different than stock is the aftermarket trailing arms and toe links which are the blue anodized bits. Good luck.

Monza355

iTrader: (3)

Great looking set up! How much power can the center section take before it goes boom? It has to be better than my 7.625" 10 bolt.

Bill

Project GatTagO

iTrader: (7)

The 3rd gen RX7 rears are similar to the 2nd gen RX7 units. The differentials are actually interchangable. Many 3rd gen owners will swap a clutch type diff from an S4 (86-88) Turbo II RX7. So both use an 8" diameter ring gear. The third gen rears do have spronger stub shafts than the second gen cars.

By the time you moneky around with swapping parts, you would be better off installing the Cobra rear.

Andrew

Skele4door

iTrader: (1)

GatTagO is probably right. You can hold a decent amount of power with the RX7 stuff as long as you keep it from axle hopping, but you are limited to 3.90 or 4.10 gears. You'll have more gearing and aftermarket options for the Cobra IRS and since you'll be doing a bunch of custom fabwork to get it to fit in another car anyways it seems more reasonable to go that route.