1985 4+3 OD Doug Nash Unit to 6 speed manual Trans
#1
1985 4+3 OD Doug Nash Unit to 6 speed manual Trans
I have an '85 Vette with the 4+3 Doug Nash OD unit (original). My dad and I have rebuilt the OD unit 3 times in 10 years and I am wanting to put a 6 Speed Manual Transmission on the car. I have inquired about a couple of pretty close fits but the cost of such a Trans is almost as much as I had paid for the car originally and just doesnt make sense to add to the car. I am trying to figure out if one of the C5 transmissions is a close replacement, 89..90...etc? If there is anyone that has made this change to an 85 Vette and has the information regarding the swap I would greatly appreciate it! My goal is to find out what trans will be a pretty close swap and then find this at junkyards, one or 2 (3)..that I can rebuild and buy whichever parts are needed and make a working transmission and then install the unit and adjust whatever is needed, shifter obviously, hoping for the drive shaft to be useable still. Any information would be greatly appreciated!! Thanks
#2
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Member Since: Mar 2012
Location: Jonesboro Georgia
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I have an '85 Vette with the 4+3 Doug Nash OD unit (original). My dad and I have rebuilt the OD unit 3 times in 10 years and I am wanting to put a 6 Speed Manual Transmission on the car. I have inquired about a couple of pretty close fits but the cost of such a Trans is almost as much as I had paid for the car originally and just doesnt make sense to add to the car. I am trying to figure out if one of the C5 transmissions is a close replacement, 89..90...etc? If there is anyone that has made this change to an 85 Vette and has the information regarding the swap I would greatly appreciate it! My goal is to find out what trans will be a pretty close swap and then find this at junkyards, one or 2 (3)..that I can rebuild and buy whichever parts are needed and make a working transmission and then install the unit and adjust whatever is needed, shifter obviously, hoping for the drive shaft to be useable still. Any information would be greatly appreciated!! Thanks
I just finished a t56 swap in my 87.. It cost me about 2500, but I spent alot on beefing up the transmission and getting a performance clutch. Realistically you could probably do the swap for 1500ish.
Good luck,
Craig
http://forums.corvetteforum.com/c4-t...completed.html
#3
#4
Le Mans Master
There is huge amount of technology in a C4, too bad the prices are so low. It's a shame, since they are really pretty good cars.
Some people have been known to scrap the car because of the cost of a trans.
Unfortunately, the car is an expensive one to repair or modify.
Some people have been known to scrap the car because of the cost of a trans.
Unfortunately, the car is an expensive one to repair or modify.
#5
#6
Burning Brakes
Wow that ZF sounds suspiciously cheap money.
You "budget" options are:
1. a running ZF with all accessories (bell housing, clutch, etc.)
CON: not cheap, expensive to fix.
PRO: easiest swap, OE, strong trans.
2. T56
CON: must use adapter(s).
PRO: cheap to repair, strong trans.
3. T5 GM World Class
CON: must use adapter. GM WC are harder to find. Not as strong. Only a 5 speed (although geared nicely)
PRO: cheap to repair. can be made stronger.
4. 700R4
CON: it's an auto
Read up on the forum about some of the trans swaps done. I was looking for a good T5 originally. Couldn't find one that was good/cheap enough (figuring I had to rebuild it). I looked at ZFs but found NOTHING under a grand (and that's with OUT a flywheel/clutch $$$). I stumbled over a relatively inexpensive T56 and jumped on it. Haven't looked back since.
You "budget" options are:
1. a running ZF with all accessories (bell housing, clutch, etc.)
CON: not cheap, expensive to fix.
PRO: easiest swap, OE, strong trans.
2. T56
CON: must use adapter(s).
PRO: cheap to repair, strong trans.
3. T5 GM World Class
CON: must use adapter. GM WC are harder to find. Not as strong. Only a 5 speed (although geared nicely)
PRO: cheap to repair. can be made stronger.
4. 700R4
CON: it's an auto
Read up on the forum about some of the trans swaps done. I was looking for a good T5 originally. Couldn't find one that was good/cheap enough (figuring I had to rebuild it). I looked at ZFs but found NOTHING under a grand (and that's with OUT a flywheel/clutch $$$). I stumbled over a relatively inexpensive T56 and jumped on it. Haven't looked back since.