BobG

I've got a friend who just bought a 63 coupe that has been back halved and is pretty much the typical Frankenstein car. Thanks to all of the fine folks at the Forum, he thinks I know something about Corvettes now, and asked me to find out what it'll take to put a big block in it (has always been a small block car). I've tried searching the archives, figuring this subject has to have been covered in depth in the past...but I was unable to find anything other than an obscure mention of a frame cutout being in the later frames that came equipped with a big block? Will he need to move the engine frame brackets, or buy some big block specific ones?

If someone has a web site, or an old post bookmarked, or just willing to share the process please post? Thanks very much.

Denney

Anything can be done with regard to swapping (with enough $). The one modification to the 65 and up frames (specifically to handle the BB) was the front cross member had an area that was sculpted (for lack of a better term) to allow clearance for the BB harmonic balancer. If the modification to BB were to be done without changing the basic cross member (i.e. shims on the mounts or something equally effective) I suspect the engine will have to sit higher in the compartment and thus ~may~ pose problems with hood clearance and drive line geometry (but will assume that the plan to convert includes a BB hood, right?) The other differences are; radiator core support, fan shroud, throttle linkage rod, and (the following depending on dimensions) possibly the bell housing, clutch throw out bearing fork, and bell crank. The obvious are also needed: exhaust manifolds, exhaust pipes. If you have a good frame shop nearby you might be able to have them replace the cross member with a later version so that you wouldn't have to worry about the clearance. HTH

achapman

A friend of mine put a 454 crate motor in a 64 Coupe, it was basically straight forward with only a minor modification (notch) made to the frame, and that was easily accomplished with a hacksaw. The motor mounts, trans, bellhousing, clutch and all was a straight bolt up, he used a low riser manifold and even the origional hood worked! Pro-Team had a pic of a 64 Coupe with a 454 in it with the original hood using a low riser aluminum manifold out on their web site not that long ago.

I am not sure about the cast iron exhaust manifolds, as my friend used BB headers. The car ran great, but.... he had to take it easy on the rear, as the SB cars do not have the beefer yokes, shafts, universals, etc. :smash:

Oops, I forgot to mention that he used the origional SB radiator, that was recored, and to date has had no overheating problems. Go for it!!! :D


[Modified by achapman, 1:41 PM 5/13/2002]

TheOman

I hope he used a 454 flywheel. The flywheel and harmonic balancer on the 454 is unique to the 454 displacement engines. Ya gotta have a 454 flywheel and balancer on a 454. Other big block parts from 427's and 396's will bolt up but your gonna have a whole lotta shaking going on if you don't have the correct flywheel and balancer.

Special machine shop balancing of the rotating assembly with heavy metal in the crank counter weights can get around the need for the flywheel and balancer from a 454 but the every day run of the mill 454 needs those unique parts.

achapman

Your right, when he purchased the 454 it came complete with flywheel, all he had to add was carb., dist., headers and a new clutch assy. :cheers:

damac

Bob G,

Unless your friend is going for all out performance with a stroker motor, he could build a big cube small block for a lot less $$. The 406, 415, or 427 small blocks are not that expensive to build and it should be pretty easy to get a streetable 500 hp/ 500 ftlbs 427 SB. He could probably get close to those #'s with a 406 and some really good heads. I had a 406 built for my car with inexpensive parts and I have 400 + HP and 500 + ftlbs out of a very mild motor.

That being said, I think the next car I build will have a 540 or 502 in it, because nothing beats cubes (except forced induction + cubes).

Mike