I have a question in regards to some cylinder heads I recently purchased and had work done to for my 1967 400 E block. The heads were bare speedmaster heads that I had Knowlton's thunderheads CNC port, and also a performance valve job on, they also cur them to 76 cc. Would this be Overkill and hurt performance with this motor running a lunati voodoo cam 227/233 @050 .511/.523, Edelbrock performer intake, headers, 10.25 compression. Thanks for any advice.

 

Flow numbers for YOUR heads?

 

I don't have them yet, they're on their way to my house. When I receive them I will post the numbers as I was told I will get a flow sheet. I'm kind of just hoping that I didn't way over do it.

 

What head gasket will you be using? Pistons are a true flat top correct?

 

That's correct true flat tops. Head gaskets will be .027 mls.

 

Ok good.

 

rjh45 - I am not a motor guy, and you certainly have the right guy in Mark (cutlassefi) looking at your numbers and configuration of your build. He'll make sure you go in the right direction.

The only reason I'm even commenting is the the build on my '67 400ci with "E" block and "C" heads is very similar to what you have described. The "C" heads were ported and polished, with performance valves, hardened seats, and hydraulic lifters. Sorry, I do not have flow numbers. It has an Engle Cam with specs very similar to the Lunati Voodoo you referenced. My Engle Cam has duration 226/230 @ .050, and lift 496/512. Edlebrock Performer Intake, Holley 750cfm Street Demon, mechanical fuel pump, full headers and 3 inch exhaust all the way to the back with Flowmasters. My motor has a pretty noticeable lopey idle, but still idles well, and the car runs strong but still has good street manners. It does have a vacuum collection system in order to power the front discs. Although the Lunati Cam you referenced is slightly more aggressive, my gut feeling is it should be a great street performer with the right tune. Just my 2-cents.

 

Overkill? No. I think that's pretty hard to do on an olds. I guess in the chevy world you can over-head a cam, but I don't think that's the case with our engine architecture and available heads.
You probably spent more than you specifically needed to in order to get the most out of that small cam, but that's a wallet problem - not a performance problem.

 

The heads can't flow that much with the stock performer intake. Its a very good intake, but flows less than a good set of ported heads. Your carb/injection tuning and ignition timing will matter a lot on how it performs.

 

RJH45- How big is the intake valve and have you received your flow number info yet?

 

Intake valve is 2.072. I dont have flow numbers yet because the heads are currently be shipped to me. Ill post them when I get the heads back. Travis at Knowlton"s said they should flow about 310 on the intake and 200 on the exhaust at .600 lift.

 

Got my heads back from Knowlton's Thunderheads today they look and flow great. Overall I'm very happy with the work done.