89notchback

iTrader: (2)

Hey guys I'm looking to swap my c-4 auto to a 2spd poweglyde.

Does anybody have any information (tips & tricks) on doing this?

If anybody could point me in the right direction that would be great. Thanks. :biggrin:

TC89LX

I did this last summer. It's not too tough when you use the right parts. I'm using an OEM GM case 'glide. From there the GM bellhousing got machined off to fit a JW SFI bell-housing for a Ford. Also in the JW conversion kit you need the Ford flexplate with the GM style converter holes and a crank hub adapter. That'll physically allow you to bolt the GM tranny to the Ford motor. For mine I upgarded to the bigger Turbo spline input shaft which means any converter that'll for a TH400 will work for me, no trick/custom parts. The transmission mount I had to customize a bit, I needed to shim up the rear as the 'glide's mounting pad is slightly higher. I simply welded a flat palet across my crossmember and drilled a new mounting hole for the single stud GM mount. I used my old Hurts Quarterstick that was reverse manual pattern with my C$ and with a bracket swap at the tranny it was able to be reused with the 2 speed. Otherwise figure on a new shifter. Some floor pan "massaging" was needed to clear the shift arm and I used an SFI body shield so some additional clearance was needed. The GM tranny is wide compared to a C4. Driveshaft, it's a different length so figure on a new piece. I ordered up a GM transmission yoke and had a local driveline company build me a shaft to my measurements that I took once it was in the car. It wasn't a big deal at all converting it over, far easier than I had first thought.

I will say this, converter selection is key to making the 2 speed perform as well as the 3 speed. Mien missed the mark the first time around. It was a bit tight. Too tight for motor runs but it loosened up nicely on the bottle. Now it's been tweaked and I'm awaiting spring to see if it all works out.

For me it was a good swap.