Vette Project. Manual to Auto?
Thread Starter
Burning Brakes
Joined: Jan 2009
Posts: 1,156
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From: New Jersey
Vette Project. Manual to Auto?
Need some more advice.
I have a number of C3s, 2 of which are projects.
My 73 I saved after being off the road for 40 years, and has been more of a project than expected, but that's ok.
I found a wrecked 74 with the interior, seats, and various items I need. The 73 is a manual and the 74 is an automatic. Since I will be transplanting the engine from the 74, I'm toying with the idea of swapping transmissions as well since all the parts are there. Is this a huge deal? It seem straight forward to me.
I know some will say don't do it, but I have other manual cars and am just working to get the 73 back up and going as a driver and trying to keep costs down.
And besides for some minor frame differences, it seems that everything from the 74 should swap over both inside and outside. Is that correct? Thanks
I have a number of C3s, 2 of which are projects.
My 73 I saved after being off the road for 40 years, and has been more of a project than expected, but that's ok.
I found a wrecked 74 with the interior, seats, and various items I need. The 73 is a manual and the 74 is an automatic. Since I will be transplanting the engine from the 74, I'm toying with the idea of swapping transmissions as well since all the parts are there. Is this a huge deal? It seem straight forward to me.
I know some will say don't do it, but I have other manual cars and am just working to get the 73 back up and going as a driver and trying to keep costs down.
And besides for some minor frame differences, it seems that everything from the 74 should swap over both inside and outside. Is that correct? Thanks
Race Director
Joined: Nov 2006
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Cruise-In VIII Veteran
Well, even if sitting a long time. One would think your manual trans is still usable.
2 things to look at, think about.
1. Converting a manual to a Automatic will decrease it's value. Although you may not give a ****.
2. Manual cars have a welded in crossmember. So putting in a Automatic will cause headaches later on if you don't cut and weld in a removable crossmember.
Me, I'd leave the trans in the car. Pull the engine only.
Drop in the replacement and install the ball for the clutch cross shaft in the replacement block.
And still have a 4 speed car that is heaps more fun to drive and has more value.
But then if value was a goal here, you'd rebuild the original engine.
None the less. Put in a auto in a sports car and just suck the fun right out of it.
2 things to look at, think about.
1. Converting a manual to a Automatic will decrease it's value. Although you may not give a ****.
2. Manual cars have a welded in crossmember. So putting in a Automatic will cause headaches later on if you don't cut and weld in a removable crossmember.
Me, I'd leave the trans in the car. Pull the engine only.
Drop in the replacement and install the ball for the clutch cross shaft in the replacement block.
And still have a 4 speed car that is heaps more fun to drive and has more value.
But then if value was a goal here, you'd rebuild the original engine.
None the less. Put in a auto in a sports car and just suck the fun right out of it.
Team Owner
Joined: Mar 2002
Posts: 44,591
Likes: 1,822
From: Huntsville AL
I don't think converting a 73 from manual to automatic is going to keep the cost down unless you are missing all the 73 manual transmission components. You are correct in the 73 manual vs 74 automatic frame differences, big one being the removable cross member and rear frame area where the 73 chrome bumpers attach. See Post #1 in below link.
Top frame is a chrome bumper frame
Bottom frame is a 1974 rubber bumper frame
Frame Link
There are a number of CF threads on this subject in both the C2 & C3 sections, some of which are pretty straight forward in the fabrication. If I was doing this I would want the body off the frame and from the sounds of it you're already in a state of disassembly with the project that after a few more bolts removed and your there.
Personally, if I had the 73 and all the manual transmission components, I would just go with that and call it a day.
Top frame is a chrome bumper frame
Bottom frame is a 1974 rubber bumper frame
Frame Link
There are a number of CF threads on this subject in both the C2 & C3 sections, some of which are pretty straight forward in the fabrication. If I was doing this I would want the body off the frame and from the sounds of it you're already in a state of disassembly with the project that after a few more bolts removed and your there.
Personally, if I had the 73 and all the manual transmission components, I would just go with that and call it a day.
