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Discussion Starter #1
Hi all,

I've got a question about different aftermarket performance heads.
I'm looking at the: Edelbrock performer RPM heads with 60cc chamber and 2.02in - 1.60 out.

Or: Ford Racing GT-40X 64cc (or 58cc) chamber 1.94 in. x 1.54 in.

Does anybody know the major advantages/disadvantages of the different heads compared to eachother? I koknw the Edelbrock is an aluminium head and therefore lighter than the cast iron Ford head (which is less prone to warpage).
I do kind of fance the ford heads, but if the Edelbrocks are better it would be a bit silly to go with the more expensive GT-40 heads.

Anyone who's got an opinion on this, please feel free to vent.

Thanks,
Matthijs
 

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The GT-40 heads have a special exhaust bolt pattern that might be a problem to find headers for your application.

There are many versions of the Edelbrock heads for small block Ford. You need the RPM version with 1.94" intake valve size for a 289 and the small 60CC combustion chamber.

I don't feel warpage is an issue so much as a faulty rumor. Most production engines have aluminum heads these days. The Edelbrock heads on my 427 have been trouble free for nine years now.
 

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I thought it was just the GT-40P castings that had the strange exahaust ports. Am I wrong?
 

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Kirk,
I know it's one of them, thought it was all but I know for sure there is no problem with the Edelbrocks.
 

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Discussion Starter #5
Summit racing says the GT-40P heads require special headers due to the orientation of the spark plugs. They don't say so for the GT-40X heads and when looking at the picture, the spark plug seems to be located rather normal on those.
But hey, I'm not the expert...

Another thing though. What makes a head better than another one? For example there are cast iron heads by Ford racing and World products.
Both 58cc chamber. 1.94 in. 3/8 in studs.
Differences: Ford has 1.54 ex. and 178 intake runners
WP has 1.60 ex. and 180cc intake runners.
What does that tell me about the flow of the heads? Does it make the ford head better for low end due to the smaller ex. valve?
And what's an intake runner? Is that the volume of the space between the manifold and the actual valve opening?

Thanks!

Cheers!
Matthijs
 

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The intake runner is the volume of the port from the face where the manifold mounts to the face of the valve.

The larger the volume the better high RPM torque is made. Unfortunately that large volume can hurt velocity in a small cubic inch motor, especially with an air cleaner choking the intake and mufflers slowing the exhaust.

The 289 also benefits from valves that are no larger than 1.94 intake / 1.60 exhaust. It can make use of larger valves if open headers and high RPM are to be a standard part of operation but it will not be as driveable in a street machine if the valve sizes are too big.

So it would seem that the Ford head is more suited to your application than the World products head.
 
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