tranny conversion
Le Mans Master
Joined: Aug 2003
Posts: 7,720
Likes: 12
From: Chattanooga TN
Originally Posted by Phil Zell
The pedal assembly is the killer, and the transmission lines will be fun also. Everything else is just everyday mechanics.
a TH350 and a muncie are the same length. TH400 is longer so you'd need a different driveshaft and crossmember mount. Either way you need pedals and clutch linkage. Then different hole in the floor, shifter, shift plate, boot besides the obvious transmission, flywheel, clutch, starter.
Safety Car
Joined: Jan 2001
Posts: 3,637
Likes: 27
From: Norwalk Ct
I just did it this past winter, a local guy was advertising a full manual kit, trans, pedals, flywheel, bellhousing, clutch linkage shifter plate all for $1200.
Swap took me about 8 hrs, hardest part was swopping the pedal assembly.
I went from a TH400 to a Super T10 and didnt have to modify anything (cross member/driveshaft).
Nick
Swap took me about 8 hrs, hardest part was swopping the pedal assembly.
I went from a TH400 to a Super T10 and didnt have to modify anything (cross member/driveshaft).
Nick
Advanced
Joined: May 2005
Posts: 99
Likes: 0
From: Lincolnton NC
I've been working on this for the last month! 
I did the pedal swap which was a beast! Instead of adding a clutch pedal, I replaced the whole assembly...which may have been simpler...had to remove the steering wheel & brake booster for access.
my screwup was in obtaining parts: almost everything I got was wrong. clutch, throwout bearing, bellhousing, clutch fork...even the ball stud in the (wrong) bellhousing! because I don't have a lift, I took mine to "the Expert"
at a transmission shop who promised me completion in 6 hours over two days....that was 2 weeks ago. I found out about the wrong parts when he couldn't adjust the clutch....after everything was installed 
My advise: dont rely on any info here or with your vendors! Make sam sure the NUMBERS are correct, use no parts from Non-CORVETTES!
For instance, the only clutch fork is 3887177, bellhousing #3899621, etc.
Depending on which tranny you use, you're probably have to get a different yoke that requires a larger (Spicer ) ujoint which means you
will need a manual driveshaft which is less than a 1/4 inch longer than the auto d-shaft but has the larger end clips for the larger yoke. (at least on my 1981)
I'd suggest going w/Hearst shifter & linkage which mounts on the tranny itself rather than on the crossmember (which expands the parts list)
Get good part number info. from GMPartsDirect.com and be very selective if you will require a "technician" or tranny shop. much luck
I did the pedal swap which was a beast! Instead of adding a clutch pedal, I replaced the whole assembly...which may have been simpler...had to remove the steering wheel & brake booster for access.my screwup was in obtaining parts: almost everything I got was wrong. clutch, throwout bearing, bellhousing, clutch fork...even the ball stud in the (wrong) bellhousing! because I don't have a lift, I took mine to "the Expert"
at a transmission shop who promised me completion in 6 hours over two days....that was 2 weeks ago. I found out about the wrong parts when he couldn't adjust the clutch....after everything was installed My advise: dont rely on any info here or with your vendors! Make sam sure the NUMBERS are correct, use no parts from Non-CORVETTES!
For instance, the only clutch fork is 3887177, bellhousing #3899621, etc.Depending on which tranny you use, you're probably have to get a different yoke that requires a larger (Spicer ) ujoint which means you
will need a manual driveshaft which is less than a 1/4 inch longer than the auto d-shaft but has the larger end clips for the larger yoke. (at least on my 1981)
I'd suggest going w/Hearst shifter & linkage which mounts on the tranny itself rather than on the crossmember (which expands the parts list)
Get good part number info. from GMPartsDirect.com and be very selective if you will require a "technician" or tranny shop. much luck
