Hello everyone. I am new to this forum. Here's a brief synopsis... I have restored old dirt bikes, tractors, etc... I have a capable shop and technical knowledge. I just finished a 1988 Daytona Shelby Z (ground up resto) as a mid-life crisis car paying homage to the one I had as a 19 yr old.

In 1993, my uncle (who has owned original 66 and 69 big block Vettes) bought a basket case 1969 Vette out from under me accidentally. In the last month he has decided the Vette should be mine to restore since it has sat in his shop since 1993 untouched since disassembly.

The car is a 69 Coupe. Factory 350/350 4 spd car in Fathom Green/black interior. The birdcage appears to be good, but the frame is bad. I have a frame from a 71 or 72 Vette that is like new. The newer model's crossmember is different than the 69's. I believe this is because one was auto and the other a manual. I cannot recall what I read about which was which.

It still sits in his shop, totally disassembled. I will be making a cradle with casters for the body while redoing it, and transferring chassis parts from one to another as I refinish them. Before I start, does anyone know the obstacles and/or fabrication I may get into with the different frame years? What about the crossmember difference?

Ok, the next question may be harsh for the purists...the car will not be numbers matching with a different frame. I have considered a 502 or 572 BB, but think perhaps it will handle better with a SB. Perhaps make the 350 a 383 stroker? Any thoughts on this? Be nice. I plan to keep the Fathom Green, perhaps a touch of pearl and a lot of clear... I do want to make it a side exhaust car. Any advice someone with more experience than I can give about restoring these cars is appreciated. Just trying to get my head around a plan...Thanks!

 

The frame difference is pretty easy- automatic cars had a removable, bolt in crossmember, and the manual trans cars did not. The bracket for the clutch cross shaft is also not on the automatic trans frames. Other than that, it's the same.

The 572 BB is a tall deck engine. It will fit, but you'll have to figure out the exhaust. When the deck gets taller, the heads get farther apart and space becomes a premium item around the steering box and the frame for exhaust. The 502 would be a drop in, the problems there are getting the correct combination of pulleys and brackets for the accessory drive.They are out there, just not cheap.

You already have all the parts for a SB install- and you can build a SB up to 454 cubic inches. Lots of guys have the 383's- built right, they are impressive.

 

If you decide to go BBC, look at after market options. BBC standard deck can go to 598 and there are a lot of nice 540 or 582 options. Take a look at nyes engines and shaffiroff for ideas.

A large cube SBC is also an option with the easiest fits at 427 or 434, as they are standard deck. 454 and 473 are common tall deck SBC options. There are too many choices, lol. Im about to finish my 65 Coupe and I have a 68 Coupe in the planning stages. Im leaning towards a large cube LSX, with a nice BBC still in contention.
Good luck with your car!

 

Depends on who's definition of "matching numbers" you use. You are likely to be the only person who would ever know the frame had been swapped.

 

exactly....

 

Hi James,
Welcome!
69 project... NICE!!!
If if you decide to change to a new motor it might be a good idea to hang on to the original because even with a replaced frame, (if well done), it will add value to the car if/when it goes along to the next owner.
Are you sure the frame can't be repaired? How rusted is it?
Good Luck!
Regards,
Alan

 

Welcome to the forum and lets see pics of the frame...I am with Alan on the hunch that it can be repaired.

Even if you needed to doctor in some pieces from a donor frame, if done right you will have a better, more correct car and as Alan said, save the motor even if you go a different route than a true restoration.

Regards, Tim

 

I'd say make sure the birdcage is fine too.
A bad frame with a good birdcage, I would not easily buy it.

Windshield frame and A-pillars is were you should look for rust.
There is a very good thread about Corvette-specific rust issue, the search tool is you best friend.

Changing a frame is doable, changing a birdcage is basically rebuilding the whole car from the ground up.

Needless to say I hope I'm wrong