MALIBU Installing a Super T10 4 speed in place of a Saginaw 3 or 4 speed in a 78-81 A body without moving the original shifter hump.

[gnvair]

I finally have my car driving and can say that the swap was a complete success. I now have a very factory looking Super T10 swap into my 78 4 speed Malibu.
I decided when I swapped out the original 305 that I would also replace the Saginaw 4 speed before I broke it. In its place is a home built nodular iron 2.88 first gear Super T10.
I went to the trouble because I wanted it to look stock which meant stock looking shifter in the stock location and I did not want to loose my original console.
The original 78-81 A body 3 and 4 speeds had a shifter location that was not in the typical location as most floor shifted GM 3 and 4 speed cars used. The shifter is mounted to the front of the tail because of the location of the seats in relation to the transmission. The Saginaw transmissions make this possible as reverse is located inside the main case where the T10 and Muncie have it located inside the tail.
I started researching what strong transmissions would permit mounting the shifter on the front of the tail. I stumbled onto the early Ford Falcon which used a T10 transmission. I purchased a Falcon Hurst Competition plus shifter and complete mounting and linkage kit. I also was able to snag a Falcon specific tail housing to experiment with. First I will post what the Saginaw 4 speed looks like with the stock shifter.

 

[gnvair]

Next I started collecting Super T10 parts. I bought a complete 86 4+3 set up from an 86 Corvette. I sold the over drive unit and specific parts. I ended up with a perfect gear set as well as a case and side cover. I also bought a blown up nodular iron Super T10 that donated the case and mid plate as well as other small items.
I first put together a mock up transmission using the aluminum case and an aluminum mid plate and Falcon tail. This way I could work easily on the bench and test fit it in the car without too much trouble. I also put a shifter on it to test fit it in the car. The Falcon tail is longer and smaller for the small Ford output shaft. I was originally planning to duplicate the mounting stand offs on an original aluminum Super T10 tail. This all turned out to be a big fail as the thick aluminum mounting plate put the shifter way over to the left. It would not clear the floor. So scratch the first attempt.

 

[gnvair]

I started staring at the Super T10 on my bench and trying to brain storm what could be done to get this to work. I started by removing the steel shifter mounting plate from the Saginaw and seeing how it could fit on the Super T10. First with clamps and just on there loosely. I used the casting parting line on the top of the tail as a measuring point. I found that I could make the original steel plate work. I started by cutting some 1/4" thick aluminum plate and made an attachment point at the front mounting the shifter plate to the upper left side mounting bolt and used another 3/8" bolt to attach it to another hole drilled into the top of the plate. Things started falling into place once I had it bolted to the front.
I found that the plate has to be offset to the left by 1/2"
I then took some measurements and used a piece of 1/2 aluminum plate to make a spacer and attachment point for the rear of the steel shifter plate. This required drilling and counter sinking the upper bolt that attaches the aluminum plate to the tail. I also counter sunk the lower bolt because my OCD kicked 😉
The other 2 holes that mount the steel plate to the aluminum plate were drilled and tapped 3/8-16.

 

[gnvair]

Now that I have the plate firmly mounted it was time to work on the shifter. I originally was going to use the Falcon shifter but found the 1-2 and 3-4 levers were too long and would not clear the reverse shifter shaft on the tail. I looked at the shifters I had. I found the factory 78-81 A body Hurst shifters I had utilized nice short levers that cleared the reverse shifter shaft perfectly (or I should say with bare minimum clearance). What I did was build a hybrid shifter using the following:
after market Hurst Competition plus outer housings with positive stop bolts.
straight Hurst shifter lever with bolt on provision (rather than the push in lever provision that the factory used).
78-81 A body 1-2 and 3-4 shifter levers.
Ford Falcon Hurst reverse lever.
This set up works perfectly!
I found a round profile chrome Hurst shifter lever on Ebay that looks very similar to the factory 78-81 A body Hurst lever but is shorter. I drilled it so it would bolt to the lower lever.
I found clearance tight on the original upper left hand tail mounting bolt and replaced it with a socket head cap screw. I also am including the pic of the clearance between 1-2 shift lever and the reverse shifter shaft casting on the tail. Its close!

 

[gnvair]

I next worked on the shifter rods and levers on the side of the transmission. I once again looked at what I had. I used all 3 Hurst rods from the Falcon shifter. I used a pair of factory 77-81 F body 1-2 and 3-4 levers. Each lever had to be slightly "tweaked". The rods require a bunch of tweaking to make sure the did not contact each other AND moved squarely in the full range of motion. The reverse rod was used as is. I did have to make my own reverse lever. I made an aluminum prototype and verified it worked. Then I tried bending it out of 3/16" steel and it cracked an broke. I ended up making it out of 1/8" steel which was easier to work with. I added a washer to take of the clearance because of the thinner thickness.

 

[gnvair]

I wanted to have function back up lights and did not want to cut my original harness. I used the flat mounting plate in the Falcon Hurst shifter kit that is attached to the back of the shifter under the positive stop adjustment bolt. I started researching back up light switches. I found one for a 62-65 Ford (yes a Ford!). It fit perfectly. I cut the Ford connector off and crimped on 2 male spade connectors that plug into my original back up light harness. I also used the back up light wiring harness clips from the Saginaw and installed them under the side cover bolts on the Super T10.

 

[gnvair]

Final product prior to installation in the car.

 

[gnvair]

Installing it in the car. Hit some small snags. First with the points on my rear aluminum adapter plate. I took the points off the top. I also did the bottom removing some extraneous material.

 

[ssn696]

Nice write up. What rear gears are you using with ST10?

...and now, with a little time travel, I can answer my own question:

That is awsome work you did to make it fit and the gears in the 5 ring BW (2.88 1.74 1.33 1.00) will work great with the 3.23 rear end...nice job

 

[gnvair]

Had to make a few more tweaks. The steel shifter plate need some material removed to clear the opening in the floor.