Im converting to a G50, I need some help.
 

So I thought long and hard about how I was going to fix my car with a tranny that would be going in for its third rebuild. I made the decision to convert the car to a G50 transmissin. In fact I picked one up off ebay for $1999 with 54k miles. Not bad huh.

I know exactly the method that I will use. I will be shortening the bellhousing and mainshaft. The questiong is, how much exactly should the two parts be shortened by? Ive heard between 24 and 28mm and I also heard the horrors of shortening too much. Now I know a very reputable machinist and I want to give him the exact measurements so it would be a good job.

I understand that this is the very beginning of a long a hard process, so expect further posts from me and lots of pictures as I will be documenting the whole thing!

The bellhousing and mainshaft are normally shortened by 28mm. It may be that some guys have found 24mm to be a better amount to remove from the early mainshaft. The later model mainshaft has more meat, which allows extending the splines a bit.

Thanks geary for responding. Now I dont have my transmission here yet to take measurements, its currently being shipped. So would cutting 28mm off the bellhousing make the base of the transmission right where that middle ridge line starts?

I am fitting a 6 speed G50 to my '89 project car, been fooling around wiht flywheels to determine the maximum that can be trimmed (the 6 speed is longer). Once I get my C2 Supercup single mass flywheel, I will be measuring starter/ring gear distances as well as checking the splines and clutch actuation.

I suspect the number is the 28mm that has been mentioned, it looks about right and has been quoted several times (IN PRINT....so it must be true!!). I get a little concerned if you trim any past that middle ring as I suspect that there is some strength required where the transmission mates up to the engine case.....

Dennis