4+3 to T-56 conversion?
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Joined: Oct 2004
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4+3 to T-56 conversion?
I am thinking about replacing my worn out 4+3 with a T-56, mainly because the only parts I can find for the 4+3 are outragously expensive. I know that the conversion can be done, but I'd like to hear from someone that has done it. Would like to know how had the switch was and if it was worth it.
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
the biggest hurdle is the tailshaft housing. It is drilled for a Cbeam, but it's backwards to the C4. This requires a bracket be made to bring it back around.
Keisler Engineering, forum vendor, has the Tremec TKO kits. It's a 5spd kit with everything for easy swap and bolt in.
It ain't cheap, but, it's complete!!! No guessing, no parts hunting! Just under $3k.... as I said, not cheap. I guess there is a warrantee... and it uses your current stock clutch.
The other option is the ZF6 conversion. It's real problem is a modification to the tunnel. Otherwise, it slides right in. The cost is about the same, but the tranny is much stronger than a stock T56.
Keisler Engineering, forum vendor, has the Tremec TKO kits. It's a 5spd kit with everything for easy swap and bolt in.
It ain't cheap, but, it's complete!!! No guessing, no parts hunting! Just under $3k.... as I said, not cheap. I guess there is a warrantee... and it uses your current stock clutch.
The other option is the ZF6 conversion. It's real problem is a modification to the tunnel. Otherwise, it slides right in. The cost is about the same, but the tranny is much stronger than a stock T56.
Instructor
Joined: Mar 2003
Posts: 187
Likes: 0
From: Aztec NM
I don't know about a 4+3 conversion to T-56 but I did a 700R4 to T-56 conversion in my 84. It wasn't a walk in the park, but it wasn't as bad as I thought it would be. The hardest part was getting the shifter to come up in the right place for a 4+3 shifter plate. Mounting it in the car wasn't that hard at all. As far as strength goes, it depends on who you ask. I think the ZF is a great transmission but I think the T56 will take alot more than folks give it credit for. If you price them on Ebay, the ZF is anywhere from 600-1000 dollars more, and if you ever do need repair on your ZF, it's much more expensive to fix. I looked for a ZF first because the swap would have been easier. But when I stumbled over a T56 that was under a grand (complete), I decided to give it a try instead. I've been pretty hard on it and have had no problems at all with the transmission, but I have yet to find the right electronic adapter to make my speedometer work.
Burning Brakes
Joined: Jan 2002
Posts: 1,228
Likes: 1
From: Dallas Texas
Yeah, I'd say go for the TKO 5 speed from Tremec. It can handle up to 600 ft/lbs and at that rating, 5th gear can be had in 0.64 and 0.82. Much stronger than the T56 and much cheaper to rebuild than the ZF6. Plus for 1700 you can have a NEW transmission instead of someone's 60k mile ZF6.
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
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