TH400 to Manual Tranny Swap

[L82Shark75]

I have a 75 with a Th400 trans. Has anyone done a manual swap? What mods need to done(i.e. crossmember fabrication, etc.) I was thinking of going with a T-10.

Thanx

 

[Cream79L82]

If you are looking for some info to read up on, there are some great links on a similar thread I had. Go there and scroll down and you'll find some good stuff.

stick shift swap threads

 

[69MyWay]

There are many things to consider.

Do a search on the C3 section and you will find a variety of past threads much like the one noted above.

It can be done, but it will cost you a chunk of change to make it 100% complete. Mostly for the little small aggravating things.

To me the biggest expense is not so much the transmission, as all the little stuff--stick shift flywheel, pilot bushing (in place), clutch, pressure plate, release bearing, welding the pivot on the frame for the Z bar, and or going up to a hydraulic like I did, pedals, brackets, springs, mounts, shifter linkage, center console changes, etc. etc. etc.

The nice part is that an automatic frame has a bolt up X member so the swap is easier. The stock stick frames have the x member welded into place which makes servicing them a pain in the butt!

 

[klb76]

A possible idea here... I am thinking about going the opposite direction, I am looking to drop an automatic into my RPO m-21 4 speed.... I wanna go with the 700R4 but my mechanic is trying to talk me into using a th400, he thinks the 700R4s are junk.... which i think alot of members disagree strongly... but that is beside the point... depending on when you are planning to do the swap we might be able to trade parts minus the tranny, I am in the same boat because i need all new pedals/shifter/blah blah blah too.... just an idea... let me know what you think...

klb

 

[L82Shark75]

Well thanx for the info. guys. I actually just dropped the trans last night. It looks like the front and rear seals are shot. Now that the trans is out, I started thinking. Damn I wish I had a 4 speed. The vette is really a dog off the line. She doesn't start to really move until after 40 mph. My other car, a Pontiac Trans Am WS6 w/ 6 speed manual, would blow the doors off my vette without a doubt. But no way in hell am I gonna try working on that car with all the computerized junk in that engine. Did anyone know that 1975 L-82 engine was one of the weakest ever built? Just my luck, right! :crazy But don't get me wrong she does have potential! I would be interested in exchanging parts for the manual, but I still have no idea where to start, or what trans to get. I only said T-10 because I think that was the original 4-speed for that year. I may be wrong, though. I'm still in that research phase. Thanx again guys

 

[klb76]

I think most others will agree that if you want a good manual transmission and the funds allow it the richmond six speed is the best bang for the buck... you might want to check this out, i found it pretty informative...

http://www.corvettefaq.com/c3/Trannys1963_1982.mht

also http://www.corvettefaq.com has a lot of good info on trannys...

klb

 

[Evolution1980]

My other car, a Pontiac Trans Am WS6 w/ 6 speed manual, would blow the doors off my vette without a doubt.

You L-82 will never beat the WS6. However...I can say that the ZZ4 in my '80 did successfully walk away from a WS6 at full throttle. And my car has a worn torque converter and TH350 slushbox! Next year when I put in the 700R4 (beefed up, of course) with a new torque converter, a WS6 will be even less competition. Just something for you to think about....

 

[L82Shark75]

Evoultion,

ZZ4, Beefed up 700r4, Supercharged!!!!!!
Just an additional thing to think about. The Z06's will be left in the dust! .

I saw your quarter mile run, by the way. Awesome!!
Wish my vette could do that.

 

[Evolution1980]

...Supercharged!!!!!! Just an additional thing to think about.

Believe me, It's crossed my mind! But two issues. 1) Where to put it. 2)I'd have to lower my compression. The ZZ4 is 10:1. Don't know if I feel like making those mods right now...