What do I need to go from a THAuto back to a M21 4spd?
10-12-2003, 08:26 PM
#1
Burning Brakes
Thread Starter
What do I need to go from a THAuto back to a M21 4spd?
My '69 started out life as a 427/435hp with a 4spd...there's a boot for the clutch pedal that's still in the firewall. Now it is a '73 454 with a -TH350- . While the tranny shifts fine, I'd rather go back to a 4-spd.
What is the laundry list of parts I'll need to go back to a M21 (or should I go M20 or M22?) Any tips or tricks? Anyone have a good source for these parts (or have these parts that would be willing to sell/partial trade for the TH350?)
Thanks,
Sam
What is the laundry list of parts I'll need to go back to a M21 (or should I go M20 or M22?) Any tips or tricks? Anyone have a good source for these parts (or have these parts that would be willing to sell/partial trade for the TH350?)
Thanks,
Sam
10-12-2003, 10:09 PM
#2
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Re: What do I need to go from a THAuto back to a M21 4spd? (sammyb)
Sammy, if I were you I'd really consider a 5 speed or a 6 speed instead of a 4 speed.
Contact Gary Gruhala at http://www.gruhala.com/showSection.asp?sectionId=2
He can probably set you up with the all the hardware you need for the swap.
Contact Gary Gruhala at http://www.gruhala.com/showSection.asp?sectionId=2
He can probably set you up with the all the hardware you need for the swap.
10-12-2003, 11:27 PM
#3
Burning Brakes
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Re: What do I need to go from a THAuto back to a M21 4spd? (Smokehouse69)
Since this is not a daily driver, I'm trying to be as stock as possible, so no 5 or 6 spd. Had a Richmond in my '70 and I hated it.
10-13-2003, 01:56 AM
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Re: What do I need to go from a THAuto back to a M21 4spd? (sammyb)
Hello Sam,
A bunch of years ago I swapped my TH-400 for a Muncie 4-speed (M20). My 69 was an auto from the start and I broke it.
I already had an assembly manual so I just went through and listed all of the parts needed for the conversion. It took me one year(not working very hard, the car was still driveable) to gather the parts and two weekends to make the conversion. One of those weekends was just to get the pedals installed and the clutch cross-shaft bracket welded to the frame. The pedal installation was the most difficult part of the conversion. All that you need is a manual trans clutch and brake pedal. The bushings and things are the same for both an auto and a manual. The whole left side of the dash has to come out. :eek:
Then you need the complete clutch linkage. The pushrod from the pedal to cross-shaft. The shaft and the rod from the cross to the clutch fork. Don't forget the three linkage springs and the support ***** and seals for the cross-shaft.
Then a flywheel, clutch, bell housing and clutch fork. If you have a TH-350, I think its rear mount is in the same location as a Muncie. The drive yoke may be the same too.
You need different top and bottom boots for the shifter and of course a shifter and rods. The bottom boot is smaller on a 4-speed than with a auto shifter. I fabricated a piece of sheet aluminum that adapted the smaller boot to the bigger hole in the trans tunnel.
The console plate is different too. That was the hardest part to find when I converted it. I think you can get repro plates now.
You also need a different lower speedo cable. The auto's speedo drive is on the left and the manual is on the right.
I went with factory parts for everything. I felt that it would make the job easier and I was more confident that everything would fit and work properly if they were all the factory engineered parts.
It's getting close to bed time so I might be missing a couple of things. But I did cover the major stuff.
The fact that the car is designed to have a manual trans, makes the job very easy. I did not run into any problems with parts fitting or interferring. It all just worked. I drive the car a lot too, so reliability has always been paramount.
Let me know if you have other questions. I would happy to try and help out more.
Best of luck, :cheers:
SharkPilot :steering:
A bunch of years ago I swapped my TH-400 for a Muncie 4-speed (M20). My 69 was an auto from the start and I broke it.
I already had an assembly manual so I just went through and listed all of the parts needed for the conversion. It took me one year(not working very hard, the car was still driveable) to gather the parts and two weekends to make the conversion. One of those weekends was just to get the pedals installed and the clutch cross-shaft bracket welded to the frame. The pedal installation was the most difficult part of the conversion. All that you need is a manual trans clutch and brake pedal. The bushings and things are the same for both an auto and a manual. The whole left side of the dash has to come out. :eek:
Then you need the complete clutch linkage. The pushrod from the pedal to cross-shaft. The shaft and the rod from the cross to the clutch fork. Don't forget the three linkage springs and the support ***** and seals for the cross-shaft.
Then a flywheel, clutch, bell housing and clutch fork. If you have a TH-350, I think its rear mount is in the same location as a Muncie. The drive yoke may be the same too.
You need different top and bottom boots for the shifter and of course a shifter and rods. The bottom boot is smaller on a 4-speed than with a auto shifter. I fabricated a piece of sheet aluminum that adapted the smaller boot to the bigger hole in the trans tunnel.
The console plate is different too. That was the hardest part to find when I converted it. I think you can get repro plates now.
You also need a different lower speedo cable. The auto's speedo drive is on the left and the manual is on the right.
I went with factory parts for everything. I felt that it would make the job easier and I was more confident that everything would fit and work properly if they were all the factory engineered parts.
It's getting close to bed time so I might be missing a couple of things. But I did cover the major stuff.
The fact that the car is designed to have a manual trans, makes the job very easy. I did not run into any problems with parts fitting or interferring. It all just worked. I drive the car a lot too, so reliability has always been paramount.
Let me know if you have other questions. I would happy to try and help out more.
Best of luck, :cheers:
SharkPilot :steering: