t50 b transmission to t50 a bell housing

corolla_alan
Posts: 8
Joined: Wed May 21, 2014 3:58 pm
Location: boise, id

t50 b transmission to t50 a bell housing

Postby corolla_alan » Wed May 21, 2014 4:35 pm

I'm upgrading my '77 corolla TE31's T40 to a T50b GT-s transmission. The bearings are larger in the T50b trans than the T40/T50a and do not clear the bell housing. I need the depth and diameter of the bearing pockets. Also the engine flange to transmission flange measurement would help me decide if i need to build a spacer or mill my bell housing

My question is: Does anyone have these numbers or have a loose 4AG/4AC GT-s/SR-5 bell housing and a depth micrometer/inside micrometer handy?

To my knowledge the T40/T50a are identical other than the obvious 5th gear in the T50a. The difference between the T50a and T50b are main bearing size, shifter location(and associated shift bars) and output shaft spline count. :)
No, I can't leave it stock :)

corolla_alan
Posts: 8
Joined: Wed May 21, 2014 3:58 pm
Location: boise, id

Re: t50 b transmission to t50 a bell housing

Postby corolla_alan » Sun May 25, 2014 3:29 am

Looks like I am on my own with this. :(
Currently I took some numbers from my T50a and compared them to the T50b. I am worried about the bearing retainer screws interfering with the bearing and bearing snap ring.
I may also need to fabricate a ring to fill the gap between the bell housing and around the retainer after milling or maby I'll only mill to the depth i need.
I'll post as i progress on my work, i may need to find a GT-s bearing retainer.
If i fail, i have 2 more bell housings to choose from. :roll:
Last edited by corolla_alan on Wed May 28, 2014 9:55 pm, edited 1 time in total.
No, I can't leave it stock :)

corolla_alan
Posts: 8
Joined: Wed May 21, 2014 3:58 pm
Location: boise, id

Re: t50 b transmission to t50 a bell housing

Postby corolla_alan » Wed May 28, 2014 9:39 pm

Today I milled my bell housing.
I opened up the bearing pocket to 2.678" dia. X .300" depth.
Then milled the retaining clip pocket to 2.825" dia. X .081" deep. New retaining clip pocket does not interfere with bearing retainer screws, but it does get close :). Also i decided against milling bearing pocket through so retainer would still be a slip fit and help center in the bell housing.
Tonite when i get home I'll try it on and see how it fits. Should be a loose slip fit :)
Last edited by corolla_alan on Wed May 28, 2014 10:04 pm, edited 1 time in total.
No, I can't leave it stock :)

corolla_alan
Posts: 8
Joined: Wed May 21, 2014 3:58 pm
Location: boise, id

Re: t50 b transmission to t50 a bell housing

Postby corolla_alan » Wed May 28, 2014 9:52 pm

On monday i talked with randy davis of brd racing and he filled me in about the t series transmissions.
There were late and early T50 tranys. I have the early 70-76 T50/40 models. There were also 77-84 and 85-87 transmissions with trans model overlap to use up the leftover tranys.
Shifter location is how you can idenify year model with bell on and also bearing diameter with bell housing off.
Important that you buy the slip yoke with the trans due to the many differant spline counts and styles.
No, I can't leave it stock :)

corolla_alan
Posts: 8
Joined: Wed May 21, 2014 3:58 pm
Location: boise, id

Re: t50 b transmission to t50 a bell housing

Postby corolla_alan » Thu May 29, 2014 8:43 pm

Test fit the modded bell housing last night. Slid right on just like oem. .300 depth was perfect with ring in place. Now just to reattatch with new gasket made from gasket sheet. :)
No, I can't leave it stock :)

corolla_alan
Posts: 8
Joined: Wed May 21, 2014 3:58 pm
Location: boise, id

Re: t50 b transmission to t50 a bell housing

Postby corolla_alan » Sun Jul 20, 2014 10:15 pm

got it in and hooked up. just need to fix the slave cylinder and build the drive shaft. i could have used the stock GT-s shaft but there was not mounting points for the carrier bearing due to the early '77 cars having one piece shafts
No, I can't leave it stock :)