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get the Stealth heads (they will be fine on the street)

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They're gonna choke that poor thing !!

I have the cam you mention in my 440. You can afford to up the compression if you're using that cam. I have 11.5:1 compression ratio and run the car on 93 octane pump gas with no problems.

Quench Explained....

Take a coffee can ½ full of gasoline burning with slow flicking flame. Strike the can with a baseball bat and you have what I would call a “fast burn”, much like what we want in the combustion chamber. The fast burn idea helps our performance engine by shortening the overall burn time and the amount of spark lead (negative torque) dialed in with the distributor. If you go from 36 degrees total to 32 degrees total and power increases, you either shortened the burn time or just had too much timing dialed-in in the first place. If you have really shortened the burn time, you won’t need so much burning going on before Top Dead Center. Now you can retard timing and increase HP. Did you ever have an engine that didn’t seem to care what timing it had? This is not the usual case with a fast burn combustion but an old style engine with big differences in optimum timing cylinder to cylinder will need 40 degrees of timing on some and others only need 26 degrees. If you set the distributor at 34 degrees, it is likely that 4 cylinders will want more timing and 4 cylinders will want less ( V-8). Moving the timing just changes, which cylinders are doing most of the work. Go too far and some cylinders may take a vacation. Now what does quench really do? First, it kicks the burning flame front across and around the cylinder at exactly TDC in all cylinders. Even with spark scatter, the big fire happens as the tight quench blasts the 32 degree old flame around the chamber. Just as with the coffee can, big flame or small flame, hit it with a baseball bat and they are all big instantly. The need for custom cylinder-to-cylinder timing gets minimized with a good quench. The more air activity in a cylinder you have the less ignition timing you are likely to need. When you add extra head gaskets to lower compression you usually lose enough quench that it is like striking the burning coffee can with a pencil. No fire ball

This was written by By John Erb & I copied it from a really good article here..
http://www.kb-silvolite.com/article.php?action=read&A_id=39

I've been trying to do some homework and I spoke with Edelbrock tech support about their heads. They stated I would not be able to run their heads due to the spark plug angle interfering with the superstock manifolds.

I'm beginning to think running aluminum may be a problem. Not quite sure if aluminum can support the weight of the manifolds. 440source said there would not be a problem. I calculate about 10.6 cr with the source heads and their 80cc chambers. That is a little higher than I'd like to go! Anybody know if aluminum can support the weight?

The aluminum heads will be fine with the heavy manifolds.My stealths on my 440 run at 6800 and are still pulling when I shift.Rocky

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Anybody know if aluminum can support the weight?

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The stealths have helicoils in the exhaust bolt holes so that really basically turns a 3/8" bolt into nearly a 1/2" bolt which does wonders to spread the load. I wouldn't worry about it.

And since Stealths are actually 84cc the compression ratio will be closer to 10.2 or 10.3...

Randy, thanks for the interesting read. I let my builder put the 88cc eddys on my 451 low deck w/ the 440 source stroker kit & am worried about having no quench. He says its zero deck, but I'm tempted to mill the heads. I've read that CNC ported stealths flow pretty well, but would the small chamber eddys w/ CNC porting be better for his 500 build? Would the Max Wedge exhaust limit the power?

I like the Stealth heads with that build. They run so close to the Eddys on all the flowbench tests I've seen, that its reasonable to assume the performance will be nearly identical. The straight plugs are a must with the manifolds. And mostly, your build has a very stock look with the dual plane manifold and stock exhaust manifolds, the stealth heads will allow that motor to look nearly completely stock, and run like a banshee!

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I've been trying to do some homework and I spoke with Edelbrock tech support about their heads. They stated I would not be able to run their heads due to the spark plug angle interfering with the superstock manifolds.

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You can get the Eddy head with straight plugs. They are the "Mopar" head with a 452 casting #.

Closed, advertised as 84 cc.

Looks like the mopar aluminum heads are ideal, exactly like factory cast.

Are the exhaust ports and height same as factory for the 440Source Stealth heads?

Yes. They look EXACTLY like factory heads...thus, the 'Stealth' moniker.

Dave

They look like the Eddys, but say Mopar.

Exactly! That's because they are made by Edelbrock for Mopar Performance.