I need to change heads, have the Edelbrock rpm heads 88cc in my mind. The 440 block in my Challenger is considerably decked. Can anyone tell me the wall thickness of the heads on the intake side? I need to mill these surfaces to compensate the decking to make sure the intake manifold will fit.

Thanks

Do you know how much material was removed from the decks? If not your going to have to try a small cut at a time and try that, then cut somemore as needed probally Which heads are on the car now? If stock OEM iron heads measure the outer head bolt bosses thickness and maybe use that thickness( I think .990 is close to stock from Mopar when new) to cut the new ones to by contacting Edlbrock and ask them how much to cut the intake side for each CC removed from the cylinder head surfaces on those heads. Mopar use to say, I think these numbers are close, for the 906 heads, to remove .010 from the head surface for each CC reduction, for each .010 removed from the head surface to remove .012 from the intake surfaces Let us know what you find out and do

I don't think there is water out there. I don't know why you couldn't go .125" I've gone 0.060"

The flange at the bolt hole is well over 0.600"

Current heads are iron Stage 5 heads. The engine was rebuilt by Landy in the late 80s, got these heads and new pistons, among many other things. The block was decked about 0.16" (4mm, no typo!) to get good CR and a bit of quench with some Speed Pro pistons. The iron heads were milled on the intake surfaces by about 0.16"x0.123=0.20" (5mm). You can see it on the next two pics, that the wall to the intake is quite thin. But on the iron heads it never made any problem, as there seems to be enough meat. On the first pic you can see one of the valve cover mounting threads, it is very thin.



The Edelbrock rpm heads (pics taken somewhere from the web) look a bit different. First they don't have the big openings around the pushrods, just small machined holes. So for pulling the lifters one would need to unbolt the intake. No problem, would be a benefit regarding to stability in my case.

This upper side is what makes me nervous. Will this wall be thick enough for milling off 5 millimeters? Biggest problem will be at the top where I drew the marking. Because of casting draft angle the wall will probably get thicker to the bottom.


I need open chamber heads, want to switch to aluminum this time. The engine was rebuilt not long ago so I need to adapt heads to the existing pistons. Are there any other aluminum open chamber heads (for street use)? This is a mild 493 stroker.