Hey guys,

so im considering doing a motor swap in my 91 fire bird that currently has the 3.1l v6 mated to the 700r4. Ive done some reading on the transmission side of the swap and realized that i will need to buy a 700r4 from a v8 car since the bellhousing cant be switched out.
I was wondering if id also need to get a different drive-shaft (do the v6 and v8 cars have different lengths?), and if i did get a new drive-shaft, would it fit with my stock rear end?

thanks for the help

 

Shaft is the same.

 

Externally only the bellhousing shape is different.

You could use a T700 /4L60 from any V8 (not only a 3rd Gen ) and just swap over the 3rd Gen tailshaft housing from your V6 trans that mounts the torque arm

 

The F-body's V8s have different internals than passenger cars, trucks, ect. Not 100% sure on the differences, but the F-body transmission have more aggressive characteristics that you want in a sporty car.

 

iv heard vette trans are a little better then ours.... i have on in mine, it definatly feels differenent, wayyy different then an lg4 car...

 

Thanks for the answers. I guess im gonna hold off on an engine swap until i can find a good trans to go with it.

 

The internals are the same , the shift calibrations are different.
A shift kit easily changes any trans so you don't need to buy a "3rd Gen " trans

 

Would a shift kit perform the same way in either a fbody or non-fbody trans? As in it wouldnt matter where I got the trans from?

 

From the factory each trans is setup ( calibrated ) for the intended use so obviously one from a truck would say , shift up at lower RPM than one for a Vette

A shift kit changes all that; the better ones give you options
http://www.summitracing.com/int/part...0235/overview/
http://www.summitracing.com/int/part...0239/overview/

 

Awesome, thanks for the links. Im gonna keep my eye out for a V8 700R4 now. I plan on doing this swap in the summer, but im trying to get an engine and trans before hand so i can build them up.
Would my speedo need to be changed if I picked up a v8 700r4?

Thanks for all the information guys, much appreciated!

 

You install the speedo parts from your trans into the new one

If the drive gear ( green gear in pic ) on the output shaft is different it is easily changed when you have the tailshaft housing off for the swap

 

This isn't really true. A shift kit changes the way a trans shifts for performance or durability, it doesn't change when it shifts as that is up to the shift valves and governor. Go throw a truck calibrated valve body in with a shift kit, you will not be happy.