Performer RPM/383 question

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bb489ss

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First off, thank you for all of the responses to my initial questions about my new Dart/383 I recently bought.
My question is this. Currently there is a Holley Strip Dominator and Demon 650 Vac secondary carb on motor. I really think I want to change that to a Holley 750 DP and Edelbrock Performer RPM manifold since this will not see much, if any track time. The heads have been milled 0.060. If I get the RPM, how much will need to be milled off the intake to fit correctly? I appreciate everyones responses in advance!! Thank you!! (Yes, I am a chevy guy that has turned to "THE DARK SIDE"):finga:
 
Welcome to the dark side. We also have ice cream!

IMO. The RPM intake is a great choice. 750 CFM's is a good Size carb for a 383, stock or well modified. To use a DP carb with a auto trans car, the at should be able to handle a W.O.T. which may require a decent rear ratio and more than average converter. They. An be a little hard to dial in otherwise.
 
I have a 727 rebuilt with a Dana 60 rear and 4.10 gears. 2400 converter. But regarding the RPM, how much do I need to mill off of it to match the heads that have already been milled down 0.060? Thanks.
 
For every .010" off the combustion chamber side, you must mill .0123 off the intake side or in your case .074".
 
Ok, so that is .074" off the actual intake manifold, correct?

Any combination of .074" off the head or intake manifold. You could take the whole .074" from the intake manifold if you wish, yes.

Are you sure that none was removed from the head at the time it was milled? I always have the head milled on both surfaces when I have heads milled. There is a raised intake surface on the head that would be almost totally removed from the head if the machinist tried to equalize the head surfaces. Better yet, I just measured three stock heads and that surface is .055-.060" tall.
 
I have no idea if they did that or not. I guess I'll remove the manifold and look. If it looks like it was machined, how will I know If I need to remove anymore? I assume if the new intake and head bolt holes line up, then it was milled?
 
One other thing to note is that the performer carb flange is 1 inch taller than the Holley flange. Consider this for hood clearance.
 
Thanks. I have a 6-pack hood with that big scoop so I think I should be ok. Demon Seed, can you review my other post on "whistling" and give me some of your advice/knowledge? As well as anyone else please??
 
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