I was told it was completely rebuilt and blue printed. Runs rlly strong, I want to know about how much those heads bumped up the cr. I have the th350 behind it right now. I am going to run a 200 4r, what gear ratio should i run with it. Setup is in my 84 cutlass, originally had 307 w/ 200r4. Will the original 7.5 axle b ok as far as power and fuel economy.

 

Heads don't "bump up" Cr, it is the combination of bore, stroke, gasket, piston and head volume, piston depth. All things being equal, the #4s are 4 cc +/- smaller than the 350 heads. But since it was rebuilt and the pistons changed, all bets are off.

 

so you r sayin the only way to know for sure is to take off one of the heads and thats wat i was talkin about was head volume

 

Also curious about how well they flow. Are they better or worse?

 

The only way to know the true compression is to measure everything; piston dish/dome, distance piston sits in or out of bore, bore, head volume, gasket volume. We can assume stroke is stock. As for flow, depends on who you talk to, IMO pretty close to 69-72 350 heads.

 

I am sayin that the easiest way to know would be to look at the spec sheet for the motor.
Since it was blueprinted, all of the measurements and clearances were written down, and they gave you that information with the motor, right?
Just look up the piston model, dish volume (if any), deck height, bore, stroke, and head gasket height and you should have your answer.
You DID get a blueprint with your "blue printed" motor, right?

- Eric

 

I got the motor out of a g body cutlass that was completely redone. It belonged to a rich kid who got drunk one night and decided to take it on some back roads speedin. Long story short he hit a set of rail road tracks and took out the suspension. I got the engine and tranns for $600 and everything was brand new underthe hood as far as hoes gaskets and silicone. I take it as I got lucky but, I dont have the spec sheet but i do believe it was rebuilt. It would just b nice to know wat the specs were. I know its not stock. Im goin to try to post a video on youtube tomorrow i will post it on here.

 

NOW I'm sayin that the only way to have any idea at all what you've got is to take it apart (and if it runs well now, that might not be a good idea...).

Either: a) Previous owner spent a lot of money for a great build, -or-
b) Previous owner had more money than brains, spent a lot of money, and got screwed.

You'll never know unless you take it apart, and essentially "re-blueprint" it.

Of course, as we grow older, we understand that some things are better left unknown.

- Eric

 

If you know the 'rich kid', ask him for the sheet, or the shop that did the work - you could be surprised!

 

I guess I will Never know lol but after i put some heards and a rpm performer intake on it i will have it dynoed