85 automatic to 4+3 conversion
Thread Starter
Instructor
Joined: Nov 2006
Posts: 228
Likes: 40
From: Uxbridge Massachusetts
85 automatic to 4+3 conversion
Good afternoon, I did a quick search, has anyone done this conversion to their 85 vette? Besides the parts, what other issues are involved? Thanks in advance.
Melting Slicks
Joined: May 2014
Posts: 2,891
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From: New Port Richey FL
Last edited by s carter; Jan 16, 2023 at 05:02 PM.
Melting Slicks
Joined: Mar 2002
Posts: 2,874
Likes: 764
From: Sligo PA
Unless Massachusetts is like Pennsylvania and manual Vettes are extremely rare I would say sell the car and buy a manual. If you just want a basic 4+3 and don't intend on building a fast car then that's your best option.
I wonder though why you want a 4+3? I kind of get wanting a manual trans but it just never seemed worth it to me to swap one. If you had to you could always throw a manual valve body in your 700r4 with a ratchet shiftier and go have fun. Now of course if you want to do some kind of stock class autocross racing then I completely understand the need for a manual trans. But if that's the case I would sell the car and look for a 4+3 car with the Z51 option.
I wonder though why you want a 4+3? I kind of get wanting a manual trans but it just never seemed worth it to me to swap one. If you had to you could always throw a manual valve body in your 700r4 with a ratchet shiftier and go have fun. Now of course if you want to do some kind of stock class autocross racing then I completely understand the need for a manual trans. But if that's the case I would sell the car and look for a 4+3 car with the Z51 option.
Oil Producer
Joined: Apr 2014
Posts: 9,367
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agree. typically if a person gets a steal of a deal on a car, but say its thevwrong trans or engine or whatever, i recommend that they clean up and sell the car the acquired cheap, for a gain, and roll that into the car they want.
thats actually easier snd cleaner and takes less work
Pro
Joined: Dec 2018
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From: Wisconsin
2023 Corvette of the Year Finalist - Modified
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I just took the 4+3 out of my 85 (to swap in the ZF.) Nothing was wrong with it aside from slight leaking at the side cover. While I had no major complaints about the 4+3, I can not for the life of me figure why someone would go to the trouble to install that transmission instead of either a ZF or one of the new TKX ones available as a complete swap kit.
The 4+3 overdrive unit has some unobtainium parts that mean once it's broken, that's the end of that transmission.
The 4+3 overdrive unit has some unobtainium parts that mean once it's broken, that's the end of that transmission.
Safety Car
Joined: Oct 2007
Posts: 4,426
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From: Pennsylvania
I just took the 4+3 out of my 85 (to swap in the ZF.) Nothing was wrong with it aside from slight leaking at the side cover. While I had no major complaints about the 4+3, I can not for the life of me figure why someone would go to the trouble to install that transmission instead of either a ZF or one of the new TKX ones available as a complete swap kit.
The 4+3 overdrive unit has some unobtainium parts that mean once it's broken, that's the end of that transmission.
The 4+3 overdrive unit has some unobtainium parts that mean once it's broken, that's the end of that transmission.
Sorry, but I find that that's not entirely true about the parts not being available. I've owned my 1985 4+3 for 17 years now and have never found any problems finding any parts I need.
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Pro
Joined: Dec 2018
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From: Wisconsin
2023 Corvette of the Year Finalist - Modified
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That is what I was referring to. As far as the 4 speed portion: it's just a Super T10. Those parts should be pretty easy to find.