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Can anyone tell me if these close chambered heads can be used with the 396/375 horse pistons? They are domed pistons and I think the Speed Pro number is L2240 or L2242. I know there is no piston valve clearance problems with the cam I'm using. Thanks.
 

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The 375 engines all had closed chamber heads, sq ports, all forged internals, and used closed chamber domed pistons to get 11-1 compression. You can use open chamber heads to drop the compression to 10-1 with closed chamber pistons. If you have open chamber pistons you must use open chamber heads or the domes of the pistons will hit the valves and heads. I have a set of stock closed chamber heads sq port bare been checked for 900 set if interested e-mail me at [email protected]
 

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3917215....67-68...oval..CLOSED..396, 427, 101cc chamber
ZL2240NF30 -21.00cc
SLP-L2242F30 -38.30cc

Bore Stroke 4.094 bore 3.76 stroke 400 is 4.124

A +.030" 4.094" bored to 4.124 with the ZL2240NF30 -21.00cc piston will give you approx a 10.2:1 Static Compression. A 278S(or SR)-10 Cam should give you approx an 8.2:1 DCR and push you easily to 6500rpm - NICE for 91 Octane ;o)

A +.030" 4.094" bored to 4.124" with the SLP-L2242F30 -38.30cc piston will give you approx a 12:37:1 Static (Too Much for Pump Gas)

And Yes; both Piston and Heads are Closed Chamber and compatible. You have to watch out using Open Chamber Heads over Closed Chamber Pistons as you usually have to relieve the Combustion Chamber and done all the time. You can not use Closed Chamber Heads over Open Chamber Pistons.

Play around with P. Kelley's DCR Calculator to help Select a Cam: http://www.empirenet.com/pkelley2/DynamicCR.html

You should always CC the Heads to insure the Combustion Chamber Displacement and if you do not 0-Deck for a .038" Composite Gasket use a .018" Steel Shim Head Gasket keeping Quench Specs between .034" to .044".

A Holley 750DP/Edelbrock RPM with Quality Roller Rockers and you're Flying ;o)

PS: If you go for Roller Rockers, you need 2" ARP Rocker Studs. Stock OEM Studs are probably the main reason the Roller Rocker Failure.
 
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