I am always in favor of deleting automatic transmissions and turning Corvettes into sports cars (too bad GM stopped making them after 2019). I'm sure the guy you knew had fun campaigning whatever car he actually had.

But the only 1983 Corvette left on the planet has an automatic transmission. And that's not even the worst part, nor is the Crossfire engine. The worst part is that it's a C4 that the sinkhole didn't reclaim.

 

I think Ggull is the man and knows what he's talking about and I think the c4 would be a good choice as well .

 

In the last 2 years I have built an autocross C4. It has a lot of advantages. Dirt Cheap initial cost. Clam Shell Hood for way better access. Conventual Engine-Trans for less involved Clutch changes than newer Vettes. Forged Aluminum Suspension with more modern design. Stiffer Chassis (but not stiff enough) Excellent ZF6 Transmission. ABS Brakes good enough for Autocross (Not Road Racing) I consider the C4 the most user-friendly Corvette to work on. Probably the biggest disadvantage is the dated Electronics. Nobody younger than 55 can understand them. The more "Race" and the less "Street" this becomes an issue. The newer Corvettes guys treat them like Dinosaurs. There are a lot of people who just hate them.

 

https://www.ebay.com/itm/19619524758...Bk9SR9bIqvyjYw

I'm guessing this is the car laz749 is referring too. If so, I know it well. It belongs to a friend of mine, and I've crewed for him on this car dozens of times. It has no "real" race history only having been built from a street car about 10 years ago by a shop in NJ, but that also keeps the price down compared to a car with documented race history from the 70's or 80's. The car's quick, handles well, is well sorted and is very reliable. It hasn't suffered any shunts that I recall. The car has both SVRA and SCCA log books and we've raced it at Watkins Glen, NJ Motorsports Park, Lime Rock Park, Thompson Speedway, and Sebring in recent years. I've believe the engine's fresh, I know the paint is, it was just repainted last fall and hasn't been raced since. You couldn't build a competitive vintage racer for the price of that car.

Here's a link to more info and pictures of the car.

https://www.jimglasscorvette.com/vin...-for-sale.html

 

In 1986 GM introduced the revolutionary ABS Bosch Braking system in the Corvette. Not sure is if it came in any other GM Vehicle or not that year. I do think that the Bosch system might of been offered in other sports cars prior to the Corvette.

 

Sounds like a great project and alot of fun ! A few general ideas. . .

The C3 frames were discarded and literally replaced several times on all the famous race cars we know of from 68-75 and this is before rust and time. The C4 is dirt cheap these days. I have one locally for 2k and I see them from 3-7k all the time. But as was mentioned earlier the frame itself is not enough and getting it stiff enough is going to take known techniques. My conclusion for my own situation, after my cheap bone is ignored, is to go with a purpose built frame and skin it with your body and suspension of choice. The reason I came to this conclusion is because I can race it OR rebody it (C2 or C3). So you would have to determine what rules you are faced with first, budget, time frame or when you want to race and what your skillset is. Roadster Shop for example was one I was looking at where you can pick C6, C7, fiberglass leafs, coil overs, solid axel etc . . .

A convertible is also an option. Stripping a junk yard body down to the birdcage to rebuild is where you can make this decision if you go this route. Benefits are roll cage is easier and lower weight or center of gravity is a benefit. Fiberglass hardtops are easy to mold and put together with a lexan rear window.

I came to this personal conclusion upon a frame expert discussing how he would weigh a raw chassis to determine the amount of integrity lost due to UNSEEN rust. Then uncovering how often the Can Am racers were replacing frames, even the Le mans cars and teams discussed it. So it kept me from doing some really dumb things very fast as I stopped to think about it.

Here is an overview of a skilled fabricator who decided to race a Greenwood bodied C3 with a C4 donor. The C4 cost was also lowered by parts sold. Very possible to do this in a small garage with a level floor and welding skills, although this uses a C3 frame.

Here is the last episode, so you can see the finished product and if you like to view earlier episodes they are linked in the article for easy access.

Best wishes and have fun, you always get great responses and meet alot of good people along the way !

https://www.corvsport.com/diy-race-c...16-the-finale/


Here is the video that opened up my mind to the chassis. Its value carries on if you don't wreck it. You have a pro touring car when your done racing that can be rebodied or you can sell the chassis alone, we all know many need them.


edit: add video