Mopar Performance catalog / Cyl head id

[70 Challenger Lover]

I should have mentioned I had mine on a 383 using a 383 intake.

[Chryco Psycho]

Very Cool , Thanks !!

[Brads70]

One of the differences I notice right away is the spring pocket is machined  deep , like to stock dimensions for a stock length valve. One of the advantages of these heads is using a longer valve so the spring pocket is not as deep allowing you to raise the roof especially on the intake port.
Another advantage to these heads if used on a B block ( 383, 400) it it allows a 440 intake to bolt on with no spacers. Performance intakes for 440 are cheaper and more options than for a 383, 400 intake and a 440 intake has slightly more volume as well.

[Chryco Psycho]

PN P4876311
This cylinder head is an aluminum replacement unit for factory big-block heads. It incorporates 2.14-inch intake and 1.81-inch exhaust valves and is a closed chamber design. These heads weigh in at 25 pounds each, which is about half the weight of an iron head, and utilize all stock-style rockers, intakes, and exhaust manifolds or headers. Unlike Stage VI units, these heads do not require the use of intake manifold adapters.

[Brads70]

PN P4876311
This cylinder head is an aluminum replacement unit for factory big-block heads. It incorporates 2.14-inch intake and 1.81-inch exhaust valves and is a closed chamber design. These heads weigh in at 25 pounds each, which is about half the weight of an iron head, and utilize all stock-style rockers, intakes, and exhaust manifolds or headers. Unlike Stage VI units, these heads do not require the use of intake manifold adapters.

So I assume when using them on a 440 block no spacer is required but what happens when you use them on a 383,400 block? What intake fits ?

[70 Challenger Lover]

So are my heads worth keeping? I only ran them for a couple thousand miles but they produced big power gains over my 906 heads. I kept them for future builds but if they are prone to cracks, I wouldn't use them.

[Brads70]

So are my heads worth keeping? I only ran them for a couple thousand miles but they produced big power gains over my 906 heads. I kept them for future builds but if they are prone to cracks, I wouldn't use them.

If they ran a couple thousand miles I'm sure they are fine. Could you post a picture of the casting symbol under the valve cover area its a circle with an M inside I believe.That's how you tell the early castings from the later one.  My buddy that builds lots of race engines loved those heads and he is a diehard Chevy guy so to me that said something. Way better than anything stock. 

[70 Challenger Lover]

The logo is around 5/8" or so. I recall that with these heads, performer rpm, and headers, it ran super strong. When I switched back to 906 heads and stock intake, the loss of power was huge.

[Brads70]

  Looks like the later casting logo!  Same as mine

[70 Challenger Lover]

Great! I'm looking forward to using them again someday. They don't seem to be worth much with all the other heads out there but doesn't cost me anything to hang on to them.

[Chryco Psycho]

So are my heads worth keeping? I only ran them for a couple thousand miles but they produced big power gains over my 906 heads. I kept them for future builds but if they are prone to cracks, I wouldn't use them.

Good heads keep them

[aussiemark]

PN P4876311
This cylinder head is an aluminum replacement unit for factory big-block heads. It incorporates 2.14-inch intake and 1.81-inch exhaust valves and is a closed chamber design. These heads weigh in at 25 pounds each, which is about half the weight of an iron head, and utilize all stock-style rockers, intakes, and exhaust manifolds or headers. Unlike Stage VI units, these heads do not require the use of intake manifold adapters.

So I assume when using them on a 440 block no spacer is required but what happens when you use them on a 383,400 block? What intake fits ?

They are direct replacements for production cast iron heads so if they go on a 383 or 400 you can reuse your original manifolds or fit aftermarket ones for the same engine.

[70 Challenger Lover]

A Guy I know is doing a 440 build and he's considering aluminum heads like the older Mopar performance ones. If I sold him my lightly used ones all set up and ready, what is a fair price for the pair?

[aussiemark]

It is hard to put a price on them because you can't get them any more, you can buy better heads and you can buy cheaper Chinese made heads but these are genuine Mopar heads that's why I bought mine. I don't need anything too radical they will be going on an original V code car with an aluminium 6 bbl manifold so this will be a limiting factor anyway if I was to use a big 4 bbl manifold then I could use better heads but for what I want these are good I drop a bit of weight and get a bit more power. It sounds like you were using yours in a similar way if I were you I'd put them back on or just put them aside you may regret selling them.

[Brads70]

I'd say 1500-2000 at least maybe more?  I can see the spring pockets are machined for stock length valves so you can't raise the roof as much . Which is one of the best features of these heads.