906 Chamber Volume?

[SgtLee511]

I just finished my 69 HP short block 383, moving on to head work. Im getting conflicting information on the heads. Is it 79cc or what, for 906's. I see in past post claims that it is never what Chrysler documented. That is much larger as high as 88cc My issue is that I built this engine with stock flat top pistons. Believing it to be close to 79cc and plan to use the 906's as this a number matching car. Whats the real number?

 

[62 Dart Convertible]

Whats the real number?

The real number is what you CC yours at.

 

[SgtLee511]

That's kinda what I'm figuring, my machinist requested I go ahead and bring the heads in.

 

[mentor70]

i cut .030 off the bottoms of my 906s to get them in a range where i could make some power back in the day.

 

[khryslerkid]

If you're wanting to keep it period correct useing that head, I say freshen them up and slap them on. You can only do so much with stock flat top pistons and an open chamber head. The right cam and good flowing exhaust will help you the most with that combo.

 

[miller]

Unless you have the means (straight bar) to check it yourself, also have your machinist check the head surfaces, too. Deck surface on the block 'should' also be checked. I'd only take off what's needed to make it flat...same amount both heads, or decks...for a good seal.

 

[SgtLee511]

What about using the thinner head gaskets, as well

 

[miller]

Steel...copper...composite...pick your poison. The thickness of the gasket is the final 'adjustment', to get the compression ratio you want.

 

[khryslerkid]

How far "down in the hole" are you?

 

[lewtot184]

88cc and may go as high as 90cc as they came from the factory.