Auto to Manual conversion
Thread Starter
Racer
Joined: Oct 2009
Posts: 306
Likes: 45
Auto to Manual conversion
How many C3 guys have made the swap from auto to manual?
I've wanted to do it for years now, and every once and a while I really get close to just doing it. The main things keeping me from doing it are of course cost, and time/difficulty. Also, drivability crosses my mind, as far as the interior in these cars being small enough for my 6' frame without having to be working the pedals regularly, but that's not as much of a concern as I think the benefit of having a stick would greatly outweigh that.
I'm looking for anybody that's done this swap themselves to give me their input.
I currently have a built 700r4 I sourced from a 93 Camaro for what it's worth.
Edit: I'm looking to convert to a 6spd
I've wanted to do it for years now, and every once and a while I really get close to just doing it. The main things keeping me from doing it are of course cost, and time/difficulty. Also, drivability crosses my mind, as far as the interior in these cars being small enough for my 6' frame without having to be working the pedals regularly, but that's not as much of a concern as I think the benefit of having a stick would greatly outweigh that.
I'm looking for anybody that's done this swap themselves to give me their input.
- Did you get a kit from someone like Keisler/SST, or piece things together yourself?
- How hard was the swap? Much fabrication work?
- Any other advice?
I currently have a built 700r4 I sourced from a 93 Camaro for what it's worth.
Edit: I'm looking to convert to a 6spd
Last edited by 80vette21; Jul 27, 2019 at 01:43 PM.
Race Director
Joined: Jul 2004
Posts: 12,706
Likes: 329
From: Scottsdale Arizona
I’ve assemble the kit on my own but never did the swap. There are a fair number of parts needed, both big and small. It’s both the time commitment and the car down time that has kept me from doing it.
Probably the hardest job is changing the pedal assembly. Not the hardest job in the world but awkward. One of the many parts that these cars seem to have been built around.
Probably the hardest job is changing the pedal assembly. Not the hardest job in the world but awkward. One of the many parts that these cars seem to have been built around.
Thread Starter
Racer
Joined: Oct 2009
Posts: 306
Likes: 45
I’ve assemble the kit on my own but never did the swap. There are a fair number of parts needed, both big and small. It’s both the time commitment and the car down time that has kept me from doing it.
Probably the hardest job is changing the pedal assembly. Not the hardest job in the world but awkward. One of the many parts that these cars seem to have been built around.
Probably the hardest job is changing the pedal assembly. Not the hardest job in the world but awkward. One of the many parts that these cars seem to have been built around.
Race Director
Joined: Jul 2004
Posts: 12,706
Likes: 329
From: Scottsdale Arizona
Race Director
Joined: Mar 2017
Posts: 11,953
Likes: 4,510
From: Virginia
The 5 speed conversion may be easier, if you only need some OD. I've not done the conversion myself, but rather opted to buy an entire second C3 just to have a 4-speed manual. Only a year apart, and the same base L48 engine, the two are Completely different cars.
Get the manual, you won't regret it!
Get the manual, you won't regret it!
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
I have done about 10 of these swaps over the years. Always done it with a kit. Currently I have been using SST. They have great customer service and the kit is all there. The 5 speed is way easier than the 6 speed. The 6 speed is a lot larger and will require some crossmember work or a new crossmember. The pedal box is not hard to do you just have to take a lot out to get it done. The easiest thing is just remove the steering column. The dash does not have to come out. It does make it easier though if it is out. Yes it is pricey but what isn’t on these cars. You can’t drive your 401K, go enjoy your hard earned $$$. Makes the car fun to drive again.
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Pro
Joined: Oct 2009
Posts: 664
Likes: 89
From: Marysville Ohio
I also did this with the SST TKO 600 kit - It changes the character of the car, in a great way. I believe this is my favorite modification (I also have done the R&P, suspension mods and a large-cubic-inch stroker). The SST kit is complete, and makes the job much easier.
As Gordonm says, the support at SST was outstanding. I did the mechanical work over 2 weekends. It would make for a good winter/early spring project. I don't recall any fabrication work except cutting the hole in the tunnel for the shifter. I also did not remove the dash, but pulled the column and gauges. Also, access to a lift makes this much easier, but you could work around that if needed. I went with a mechanical clutch, but a lot of people like the hydraulic setup.
I believe SST has a 6 speed kit too, but you would have to check on that
As Gordonm says, the support at SST was outstanding. I did the mechanical work over 2 weekends. It would make for a good winter/early spring project. I don't recall any fabrication work except cutting the hole in the tunnel for the shifter. I also did not remove the dash, but pulled the column and gauges. Also, access to a lift makes this much easier, but you could work around that if needed. I went with a mechanical clutch, but a lot of people like the hydraulic setup.
I believe SST has a 6 speed kit too, but you would have to check on that
Melting Slicks
Joined: Jun 2011
Posts: 3,116
Likes: 598
Here is my notes for a 78 auto to a T56 magnum 6 speed.
https://www.corvetteforum.com/forums...-corvette.html
https://www.corvetteforum.com/forums...-corvette.html
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I went from racing 700r4 to tko 600 with a 4.11. The tranny cross member is correct as is the drive line.
I did the Kiesler kit. With block saver plate, 22 pound billet steel 168 tooth SFI flywheel, blow proof bell housing.
I went with a manual easy on the leg clutch made for very high HP applications. After 2 years of road racing it was in perfect condition even though I had just broken my 427s forged crankshaft.
.
I did the Kiesler kit. With block saver plate, 22 pound billet steel 168 tooth SFI flywheel, blow proof bell housing.
I went with a manual easy on the leg clutch made for very high HP applications. After 2 years of road racing it was in perfect condition even though I had just broken my 427s forged crankshaft.
.
Melting Slicks
Joined: Dec 2009
Posts: 3,233
Likes: 657
From: Thunder Bay
I swapped a TKO-600 into my '79 a few years ago and love it. I also had a 700R-4 in the car before a did the swap. Its was a huge improvement over the TH350 but I've always preferred a stick, and I'm glad I did the swap. I put the parts together myself thinking I would save a few bucks. I did, but not enough to justify the hassle. If I had it to do over again, I would find out who does the best kit, and buy it from them. I used the .64 overdrive. Also if I had it to do over, I would consider the .82 . It's a big drop from 4th to 5th with my 3.55 gears. Its great on the interstates, but I often find myself in no-man's land between 4th and 5th gear where I'm revving too high in 4th and lugging the engine in 5th.
There's nothing particularly hard about the swap, but it's a big project if you do it properly. I did mine over the winter.
There's nothing particularly hard about the swap, but it's a big project if you do it properly. I did mine over the winter.
Le Mans Master
Joined: Dec 2003
Posts: 5,381
Likes: 416
From: N J
I didn't buy a kit, instead I collected the parts I needed and swapped out the auto in my 77 to a 5 speed.
Did a prior conversion on my 68 with the same trans, a little world class T5.
Had to alter the stock rear trans mount and the exhaust mount to work with the t5, and have the driveshaft shortened.
Dropped the dash and column, bolted in the new pedals, fastened a new z bar mount to the frame and hooked up the stock linkage.
Almost 8 years ago, no problems.
Did a prior conversion on my 68 with the same trans, a little world class T5.
Had to alter the stock rear trans mount and the exhaust mount to work with the t5, and have the driveshaft shortened.
Dropped the dash and column, bolted in the new pedals, fastened a new z bar mount to the frame and hooked up the stock linkage.
Almost 8 years ago, no problems.
Racer
Joined: Jan 2011
Posts: 336
Likes: 81
From: Southeastern MASS
I bought a pedals/linkage kit from Corvette Central, it has everything I needed for my 76. I'm putting a world class T5 in it. I had to modify the trans mount and shorten the driveshaft. Luckily I'm an OK fabricator so I could handle the mount myself, welded the cross-shaft mount to the frame. I had the body off at the time, I'm thinking that part would have been pretty difficult with the body in place. I also had the whole dash/column out of the car so the pedals weren't too bad. I did this same T5 conversion to my 69 Camaro a few years ago and I really like it. And I haven't hurt the T5 behind a small block yet, either.
Peter
Peter
Drifting
Joined: Aug 2010
Posts: 1,626
Likes: 140
From: Kanuckistan
2022 C3 of the Year Finalist - Modified
Went down the thrifty (and hard) road :
Broken GM WC T5 I rebuilt in a G-Force reinforced case.
Ebay (chinese) Camaro short throw shifter I adapted AND fixed (because they are junk otherwise)
Pedal setup from Forum sale section
Cheap scattershield from Ebay.
I build my own crossmember bracket.
Had the auto driveshaft shorten at a local 4x4 shop.
90's GM truck master and slave clutch cylinder, even if I learned recently I could have gone the Z-bar way with my ls swap, oh well.
T5 rebuild is very well documented on DVD and also on youtube. Using a GM T5 allows you to use standard bellhousing but the bracket is a little more tricky to build.
Broken GM WC T5 I rebuilt in a G-Force reinforced case.
Ebay (chinese) Camaro short throw shifter I adapted AND fixed (because they are junk otherwise)
Pedal setup from Forum sale section
Cheap scattershield from Ebay.
I build my own crossmember bracket.
Had the auto driveshaft shorten at a local 4x4 shop.
90's GM truck master and slave clutch cylinder, even if I learned recently I could have gone the Z-bar way with my ls swap, oh well.
T5 rebuild is very well documented on DVD and also on youtube. Using a GM T5 allows you to use standard bellhousing but the bracket is a little more tricky to build.
Instructor
Joined: Nov 2013
Posts: 220
Likes: 17
From: Pasadena MD
I did the SST kit and have been enjoying it for two summer seasons now. The pedals were the worst part mainly due to accessibility. I did the hydraulic clutch too, well worth it! The TKO 600 is hands down the best shifting transmission I have ever had.
Race Director
Joined: Jan 2000
Posts: 12,399
Likes: 247
From: San Jose CA
It sounds like you're running an 80 'vette.
I did the swap in my 78. 75-82 cars have stamped steel floors and different pans for auto vs manual, whereas the earlier cars had fiberglass floors and a bolt in cutout for the different transmissions. So I had to do some cutting and a friend put a plate together for me to seal the hole.
That said, I did a liberty gears swap back in 2014 or so.
I'm curious how SST solves this problem. I'd love to have the floor be a bit more permanent than my current setup is.
I did the swap in my 78. 75-82 cars have stamped steel floors and different pans for auto vs manual, whereas the earlier cars had fiberglass floors and a bolt in cutout for the different transmissions. So I had to do some cutting and a friend put a plate together for me to seal the hole.
That said, I did a liberty gears swap back in 2014 or so.
I'm curious how SST solves this problem. I'd love to have the floor be a bit more permanent than my current setup is.