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It is time once again to do my thing on my 71 GTO. I have rebuilt this car several times over the past 36 years and would like some input on my latest journey. Currently configuration is as follows:
455 +.040
Eagle Rods, Ross pistons
#64 Heads with SS valves
455 HO alum intake and carb
Ultradyne 231/239 Hydraulic Cam with Roller rockers
RAIII cast headers
M22 with 3.55 rear

Prior to this rebuild the I had contemplated the then New Edelbrock heads and decided to wait and see how they worked out. Need less to say my current set up is picky on the fuel it like and can be hard starting. The question I have is will there be benefits to upgrading to aluminum heads and what choices make the most sense for weekend driving?
Any feedback is appreciated.
 

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I'm in the same position. I'm restoring a '67 that is not numbers matching. Have procured a low comp 455 but it's a 73 so the heads are no good. I think it goes without saying if you're going Edelbrock aluminum you want the 87cc ones, not the 72's. Probably also want the d ports so you can keep your RAIII cast headers.

You may also want to look at Kauffman Racing Equipment, they have 64/75/85 cc aluminum dports.

My understanding is you can go a little higher on compression with aluminum heads because they stay cooler and are more efficient. Your setup sounds a lot like what I want to do, .030 over, aluminum heads, RA exhaust, and a factory aluminum intake so I can install the '67 HO ram air pan. I also just finished my rear, I went a little taller with a 3:23 Auburn posi. Mine won't see ignition for another year or two, doing a frame off and just last weekend turned the socket wrench from loosen to tighten, long way to go.

If you install the aluminums let us know how it goes!
 

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You can run higher compression (a little higher, say 10.2:1 "or so") with aluminum heads because they do stay cooler. Running cooler however makes them LESS efficient, not more, because you're losing heat energy to the atmosphere instead of retaining it in the chambers to make power. For this reason, all other things being equal, aluminum heads will also tend to "like" a little more ignition timing than the equivalent head in cast iron.

The chamber design in the new D-Port E-heads is gorgeous. However, the port flow isn't as good as their earlier round port heads. In my opinion, this makes them "ok" for a moderate street engine but they'll run out of gas for much more than that. I understand about wanting to retain your exhaust system (D-port vs. round port), so if you want a D-port aluminum head I'd steer you over to the Kauffman's. They've got a lot better upside potential than the D-port E-heads do. Regardless of which route you take with aluminum heads, I strongly recommend buying them "bare" (no valves or springs) and then having someone who really knows their craft finish them out for you. This is because the hardware that comes with the 'ready to run' heads isn't of terrific quality. That's how they boost profit margins on those - by using 'inexpensive' (to them) parts.

My car was already set up for round-port heads, so I went the round-port E-head route, bought them bare, then had Dave Wilcox at CVMS finish them out for me and also treat them to one of his 'entry level' porting procedures. They came to me things of beauty, nicely blended everywhere, valves unshrouded, and running larger valves than would have come with them originally. They're one of the big reasons my car runs 11's at the track. :D

Bear
 

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Great info. I'm starting from scratch so I was thinking to go round port Kauffman's ( hink they call them high ports or something). They do also offer upgrades on porting and valve train. I think they have different flow options and of course price escalates. Not sure about Lifetime Goat, but mine will be strictly street so 11's not necessary (but sounds fun!).

Like I said, long time before I'm there so I have a lot of time to think about it. I heard Ames is coming out with a better / lower cost version of the cast iron ram air exhaust manifold too (D and Round) so I may be able to wait for them....
 
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