[66DAVID]

Well the motor they threw in with the car is a 73 454 block #3999289 heads # 353049 oval ports...but has a 1970 gm aluminum intake rectangular port manifold.. I took off manifold this morning to check out motor and discovered this.. Looks like a fresh rebuild..dont think they ran this yet with this manifold..Gaskets were all still fresh. WILL THIS SETUP WORK RIGHT

 

[TrannyMike]

I would think that running such a mismatch would hurt the flow. Port matching is a pretty common practice and that's with manifolds and heads that do belong together. In my opinion you should buy the correct manifold. I'm sure the difference in performance will be dramatic even without any port matching. Others here that are motor experts will tell you for sure. I'm a transmission expert, but what I've said makes sense to me from all I've read while building the few motors I've done. Good luck! :beer:

 

[LOCKJAW]

X2 what Tranny Mike posted. Flow is everything when you want to make power.

Mike, I hope you are on the mend!:secret:

 

[TrannyMike]

Mike, I hope you are on the mend!:secret:

Hey James! I'm doing much better, but still need to be careful how I move around. :beer:

Sorry about the thread jack!

 

[ccc]

i have seen this a few times and they never ran right,way down on power. the flow hitting the head surface and bouncing back fights the air trying to enter the head port.way too much turbulance in the port

 

[TrannyMike]

Well, I must have been right if Lockjaw & CCC both agree. Nuff said, get a manifold. :beer:

 

[66DAVID]

Thanks for the info guys.... Im probably gonna sell the big block anyways..I want to put a small block back in it..