BlueShift

This is just a general question to the people who have done V8 swaps in general. What transmission is used? I know that the Corvette has the rear mounted transmission so for the people who do the LS-1 swap what are they using for a transmission? Does the Rx7 transmission really mount up or is there something else used??

point5chink

i beleive the most commonly used tranny is the t56. The corvette does use a rear mounted tranny, but plenty of ls1 and ls2 cars use a forward mounted tranny. Trannys are pulled from camaro, firebird, gto, etc.

Upgrayedd

iTrader: (1)

With the LS1 (or any other LS series motor) they use the Chevy transmissions (T56 most commonly). To use an RX7 tranny you'd have to get an adaptor plate. And it just wouldn't make sense... The Chevy transmissions are much more common and thus would be easier to get parts for and in my opinion perform better with the motor.

Brian is right on, most guys are getting their motors and transmissions from a wrecked GTO, Camaro SS, or Trans Am.

1Seven4Me

iTrader: (1)

The RX transmission wouldn't last long at all behind a LSx, if it could be adapted. You're going from an engine that put out ~150 lb-ft of torque to an engine making 300 lb-ft of torque at a minimum(some put out much more depending on the mods).

The most common LSx engine used for swapping into the RX7 is the LS1 and LS6 from 98-02 camaros & firebirds, and the choice transmission is the T-56 which comes in those. the reason is mostly the fit.... the oil pan fits the crossmember almost perfectly in an FC, the accessory drive all fits under the hood, AC & PS can be retained if one desires, the intake fits under a stock NA hood, the transmission fits in the tunnels w/o major mods, shifter is in the right location(a big deal), heck even the stock throttle cable from the camaro is used (it snaps in w/o much work)....
The corvette oil pan isn't used('batwing' configuration).... but I believe Hinson has come out with a FD cradle for the LS2 'vette pan. The GTO oil pan isn't used b/c it's a front sump. The truck pans are too deep, the water pump puts the water outlet into the hood, and the truck intake is too tall(but it flows great). There are other reasons why the F-body engine/trans combo is the best choice, but these are the big ones.

One more reason the Tremac (makes the T-56 in various configurations for GM, Ford and Chrysler) T-56 is chosen is the double overdrive, 4th gear is 1:1, 5th gear is .78:1, 6th is .5:1. This allows a V-8 powered car running stock T2 gears(4.10:1) to turn the motor at a reasonable RPM going down the highway, and you get ~30 MPG doing it. One more note... the GTO T-56 has been used but the shifter sits a little further back (fits a little better in an FD from what I've read) and many don't like the shifter... it seems notchy to them. F-bodies used the T-56 from '93 to '02, but 93-97 were slightly different (behind an LT1) they can bolt up to a LSx based engine, but some mods are required to run them.

Personally, I'm using a 4L60E automatic, while the overdrive isn't .5:1; I plan on running it on the drag strip more. I can't out-shift the electronic shift system... it'll be more consistent than I ever will be, and it's about 1/2 second quicker than the manual.

One more note is that some are changing the T-2 rear out for a ford 8.8 IRS diff setup. Not cheap to do, but it's stronger and gives you more gearing choices. Manual transmissions are tough on rear ends.... basic fact. Countless swappers have broken NA rears, some have broken T2's. The gearing choices alone makes it tempting for anyone running an automatic.