Question
Race Director
Joined: Mar 2017
Posts: 11,929
Likes: 4,497
From: Virginia
79s had 3.36, 3.55, or 3.70 options. Last 3.08s were in 78. Everyone got 3.07s in 80, then the ratios got even lower to close out the C3.
https://corvettec3.ca/axle.htm
My 79 auto has a 3.55 diff. I can say from experience, blasting along at highway speeds is much better for the car than sitting in stop and go traffic.
But don't take a random website's word for it. Get info right from the source, in my signature.
https://corvettec3.ca/axle.htm
My 79 auto has a 3.55 diff. I can say from experience, blasting along at highway speeds is much better for the car than sitting in stop and go traffic.
But don't take a random website's word for it. Get info right from the source, in my signature.
Thread Starter
Intermediate
Joined: Jul 2024
Posts: 47
Likes: 11
Simple answer is yes you can drive 70-80 mph, they certainly were driven there when new.
Will your engine last as long as a new car, probably not.
Will you get 25+ mpg, absolutely not. Anything over 15 with an old, stock vette was a plus. 11-13 is where my '72 base 350, TH400, 308 was.
Looks like you have a 79. For most of the C3 run, automatics had a 308 gear with optional 355's. The '79 may have dropped the 308 and gone to the 336 for both trans. I'd have to look it up but really it doesn't make much difference between a 308 & 336.
The car was nearing the end of the run but still a car I liked. I recall looking at them new in showrooms. Probably about $9k new, give or take on the car. A lot of 79's were made, a lot had some issues. I knew a couple of people who bought them new and had a lot of warranty work done.
That was 46 years ago. Today, it is hard to find one that hasn't been worked on and in great condition. Yes, some are still out there but since you're new to these cars I would just drive it and see if you even like it. Those guys I knew who bought them, all sold or traded them in by 1980. If you do keep it and are not one to work on it, it can be a money pit. Even doing the work, they are costly. You either love them or come to hate them. Everyone is different and has a different perspective on how the car should be.
Will your engine last as long as a new car, probably not.
Will you get 25+ mpg, absolutely not. Anything over 15 with an old, stock vette was a plus. 11-13 is where my '72 base 350, TH400, 308 was.
Looks like you have a 79. For most of the C3 run, automatics had a 308 gear with optional 355's. The '79 may have dropped the 308 and gone to the 336 for both trans. I'd have to look it up but really it doesn't make much difference between a 308 & 336.
The car was nearing the end of the run but still a car I liked. I recall looking at them new in showrooms. Probably about $9k new, give or take on the car. A lot of 79's were made, a lot had some issues. I knew a couple of people who bought them new and had a lot of warranty work done.
That was 46 years ago. Today, it is hard to find one that hasn't been worked on and in great condition. Yes, some are still out there but since you're new to these cars I would just drive it and see if you even like it. Those guys I knew who bought them, all sold or traded them in by 1980. If you do keep it and are not one to work on it, it can be a money pit. Even doing the work, they are costly. You either love them or come to hate them. Everyone is different and has a different perspective on how the car should be.
I love my 79. I've had it for about 6 months now, and it's never given me any issues aside from a few small things. But it has never quit on me and actually runs like a brand new car. VERY smooth. It was either taken very good care of, or the engine was rebuilt somewhere down the line.
I think I'm gonna try putting an overdrive trans in it at some point, alongside a 383 stroker engine swap.
Thread Starter
Intermediate
Joined: Jul 2024
Posts: 47
Likes: 11
Could anyone suggest me a good overdrive tranny?
something that could handle a 383 stroker would be preferrable, as I am going to swap the L48 for the 383. (Nothing against the L48, it runs amazing, I just want more power)
something that could handle a 383 stroker would be preferrable, as I am going to swap the L48 for the 383. (Nothing against the L48, it runs amazing, I just want more power)
Race Director
Joined: Mar 2017
Posts: 11,929
Likes: 4,497
From: Virginia
Get the kit from Silver Sport Transmissions
https://www.shiftsst.com/
https://www.shiftsst.com/1968-1979-c3/c313
Melting Slicks
Joined: Apr 2021
Posts: 2,671
Likes: 2,124
From: Minnesota
Racer
Joined: Dec 2022
Posts: 300
Likes: 87
I simply don't agree with that guy above. Keep it under 80 ???
Why? The car was designed to run well over 80 for hours on end!
They did race these cars in 24hour endurance races back in the day ya know!
Yes you can re-enginer the car. But it ran just fine before you bought it!
This very thing comes up on this forum every so often. Young guys worried about spinning an engine that was designed to spin!
Just drive it!
Why? The car was designed to run well over 80 for hours on end!
They did race these cars in 24hour endurance races back in the day ya know!
Yes you can re-enginer the car. But it ran just fine before you bought it!
This very thing comes up on this forum every so often. Young guys worried about spinning an engine that was designed to spin!
Just drive it!
