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Discussion Starter #1 (Edited)
I'm currently trying to decide which head/intake combination to go with.

With KRE battling Edlebrock to be "The Man" for Pontiac aluminum heads, I'm currently in information overload!

Headers vs. Cast Iron RA type exhaust doesn't really matter to me, although I'm probably leaning toward the latter since I hear so many horror stories about trying to fit headers in a '65 GTO. With that in mind, I'm guessing D-port vs. Round Port isn't a big deal.

Planning on having Cliff go through a Quadrajet for me.

Cliff had this to say:

"How big is the intake runner on the KRE 290cfm heads? If it’s opened up to a RAIV gasket you may not be able to use a stock intake unless it’s a RAIV or 455HO."​


Tin Indian sales guy said this:

The 290 port does have a RAIV port match - required to have the head flow what it does

That being said your intake would NOT currently have a RAIV port match. Can you use your stock intake - yes you can. You would either have it port matched (openings ground open) to a RAIV gasket or you could just use the RAIV intake gasket and it would NOT be "matched". While it is ideal to be matched for what you are doing I doubt you would notice much difference if it was NOT matched. I can tell you this, the stuff certainly wasn't gasket matched from the factory!

Keep this in mind as well, unless you divorce the intake from the water cross over its hard to get good alignment of the intake pots anyway since the timing cover washer / bolt is used to pull the intake forward so that it seals with the doughnut gasket with the back of the timing cover. If you are pulling the intake forward to seal the water cross over you will never have perfect alignment. That is why people concerned with alignment divorce the water cross over from the intake.

Hope that helps"​

I welcome input.....Which heads would you go with? And I thought others might be interested in what Cliff and the Tin Indian guy or gal said.
 

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My Doug headers fit fine in my 65' convertible 4 speed .....

So back to the heads, are the KREs the way to go??? And what about recommended compression ratio ~10.X:1 ? What about lower compression (say more like 9:1) - are you really losing a lot of horsepower?
 

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Discussion Starter #3
My Doug headers fit fine in my 65' convertible 4 speed .....

So back to the heads, are the KREs the way to go??? And what about recommended compression ratio ~10.X:1 ? What about lower compression (say more like 9:1) - are you really losing a lot of horsepower?
Good to know cij, thanks. Did you install them with the engine already in or while the engine was out? Did you have to do any banging on them to get them to fit?

Not sure how much HP I'd be losing per CR point. The guys at Tin Indian said I could easily get up to 11.5:1 and still run on pump gas with their heads. My engine builder says I don't want to go that high and should stay between 9 and 10.5 max. 10.25:1 is about what the online calculator says I would get with 85cc chambers and -8cc pistons with a stroker kit of 4.155 bore and 4.25 stroke.
 

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Good to know cij, thanks. Did you install them with the engine already in or while the engine was out? Did you have to do any banging on them to get them to fit?
The engine was in the car when the headers were installed (from below) and there was no banging / bending of the headers to make them fit.
 

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The Doug headers I installed are DHE-D564C Pontiac 1964-1967 389-455 GTO, Lemans, Tempest D-Port Headers 1 3/4' Pipe 3' Collector (Ceramic Coated). I bought them from Butler Performance. As I mentioned previously, they fit nicely (tight) and were installed with the engine in the car.
 

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"If you are pulling the intake forward to seal the water cross over you will never have perfect alignment. That is why people concerned with alignment divorce the water cross over from the intake."

very true. just as importantly from a performance standpoint is that a half inch gap or so between thermostat cross over and intake manifold reduces the heat in the manifold, which gives a denser charge, which increases power. also it makes swapping manifolds so much easier.
 

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An aluminum head can run one full point more compression than an iron head, as aluminum is less thermally efficient. A 10-10.5:1 aluminum headed engine would need the same octane fuel as a 9-9.5:1 iron headed engine. To drop the compression of an aluminum headed engine into the 9:1 is to leave a lot of power and fuel economy on the table.
 
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