Combustion chamber size?

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Richie

Richie

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Hi everybody:

What combustion chamber size should a guy order 63 or 65 cc. I want 400-450 hp with promaxx heads and new 340
 
No quick answer - it depends on many things including pistons, head gasket compressed CC's, intended use, and available fuel.
 
It depends on your setup, but 2cc isn't going to make a big difference. 65'
 
So why would they have 2 parts with only a 2cc difference? Is 63 closed chamber and 65 open? I haven't found anything on that yet.
 
Yeah the 65s are open. They are for the 340 pistons that are out of the hole .018 for clearance. They have pictures of them on their website
 
in that case get the closed chamber so you can easily get some quench
that's more easily
but calculate the rest of your build- pistons, gasket
and as said above- gas, use torque cure desired (short cam-long cam)
 
Jax340Dart said:
Yeah the 65s are open. They are for the 340 pistons that are out of the hole .018 for clearance. They have pictures of them on their website
Click to expand...


They are not really open chamber either. The plug side of the chamber is closed which means you can only use a FT piston and about the most you can get he piston out of the hole is maybe .020 and that's a stretch.

Again, Vic and crew didn't do Chrysler guys any favors.
 
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yellow rose said:
They are not really open chamber either. The plug side of the chamber is closed which means you can only use a FT piston and about the most you can get he piston out of the hole is maybe .020 and that's a stretch.

Again, Vic and crew didn't do Chrysler guys any favors.
Click to expand...
I was going to get these because of their quality.. apparently they are great as far as that goes and not too expensive the other ones Dart Brodix are more. Every other brand I've come across reading about one or two things go wrong with them...sometimes. Just paranoid I guess lol



 
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I run Indy RHS Iron LAX heads. .020 flat tops above deck with an SCE .060 thick head gasket on 93 pump gas.
 
The 63cc shockers are closed chamber... they look very well made.

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65 is an open chamber and the 63 is a closed chamber? Id like to see what 2cc's is worth on an open head in chamber shape. Any pics of the chambers online?
 
There are pics online, but only the intake and exhaust side show the SBM heads.
The images of the open and closed chambers seem to be of a Ford and a BBM. :)
 
I could have gotten some pictures last week of the chamber but now they are bolted on the engine.
 
stixx said:
There are pics online, but only the intake and exhaust side show the SBM heads.
The images of the open and closed chambers seem to be of a Ford and a BBM. :)
Click to expand...
Yes, their online catalog SBM head pix are AFU! Don't go by that.
 
If what you already have an assembled 340 short block that has the pistons sticking way out above the deck........ then you may want the open chamber heads.

For basically any other scenario, you want the closed chamber heads.
 
with out of the block pistons I'd use the closed chamber with the thick gasket combo
more future proff
say you want to go with a stroker on your next build
 
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