87 Transmission Help
Thread Starter
Cruising
Joined: Sep 2017
Posts: 11
Likes: 0
From: Killingworth Connecticut
87 Transmission Help
I have a 87 corvette with the 4+3 doug nash manual transmission. I'm having a lot of problems with the overdrives right now and I was wondering how hard it would be to take a 6 spd transmission from the newer C4 corvettes and put it in my 87.
Thanks!
Thanks!
Last edited by MJG55; Sep 7, 2017 at 10:21 PM.
Racer
Joined: Nov 2010
Posts: 496
Likes: 10
4+3 overdrive
[QUOTE=MJG55;1595528584]I have a 87 corvette with the 4+3 doug nash manual transmission. I'm having a lot of problems with the overdrives right now and I was wondering how hard it would be to take a 6 spd transmission from the newer C4 corvettes and put it in my 87.
If you do decide to change over to 6sp I could use the overdrive unit. Also for parts. TIA
If you do decide to change over to 6sp I could use the overdrive unit. Also for parts. TIA
Instructor
Joined: Jan 2016
Posts: 148
Likes: 16
From: Verona KY
There are several write-ups on the forum on doing the conversion and SST Transmissions sells the complete changeover kit.
I will hopefully have my '86 back later 2day from getting the DN 4+3 replaced with a complete donor unit from Northern Corvettes in Ontario Canada.
My old unit has the OD clutch burned out but backs up fine. I picked up the special tool kit for the DN unit and I'm going to rebuild the old unit when cold weather hits.
Jonathan.....
I will hopefully have my '86 back later 2day from getting the DN 4+3 replaced with a complete donor unit from Northern Corvettes in Ontario Canada.
My old unit has the OD clutch burned out but backs up fine. I picked up the special tool kit for the DN unit and I'm going to rebuild the old unit when cold weather hits.
Jonathan.....
Oil Producer
Joined: Apr 2014
Posts: 9,371
Likes: 2,736
There are several write-ups on the forum on doing the conversion and SST Transmissions sells the complete changeover kit.
I will hopefully have my '86 back later 2day from getting the DN 4+3 replaced with a complete donor unit from Northern Corvettes in Ontario Canada.
My old unit has the OD clutch burned out but backs up fine. I picked up the special tool kit for the DN unit and I'm going to rebuild the old unit when cold weather hits.
Jonathan.....
I will hopefully have my '86 back later 2day from getting the DN 4+3 replaced with a complete donor unit from Northern Corvettes in Ontario Canada.
My old unit has the OD clutch burned out but backs up fine. I picked up the special tool kit for the DN unit and I'm going to rebuild the old unit when cold weather hits.
Jonathan.....
JW, be sure you start a thread on your rebuild. I think I'll be doing one as well.
Safety Car
Joined: Apr 2016
Posts: 4,648
Likes: 1,059
From: N.E. Ohio OH
Finalist 2020 C4 of the Year - Modified
how hard it would be to take a 6 spd transmission from the newer C4 corvettes and put it in my 87.
The 3.07 Dana 44's are a good swap in for A4 cruising cars that see lots of highway driving.
The after market transmissions have internal gear ratios that take this into account. Don't forget to include it in your estimate.
https://thevettenet.com/corvette_specs.php?year=1987
https://thevettenet.com/corvette_specs.php?year=1992
Last edited by drcook; May 17, 2019 at 08:57 AM.
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