Since I have a closed chamber piston, I can't run closed chamber heads? My pistons are not open chamber. How about running a 110 cc aluminum head from GM Performance Parts, I believe it is called the "signature series." I believe this to be my best bet, as I can buy a set for $1600. They come with 2.19" intake valves and 1.88" exhaust valves. They've got a great chamber design and look great, plus they would raise my compression. Anyone have any suggestions or imput to this head combination?

I am thinking about putting those heads on my 468 in the future, my heads are closed chamber and have the same cc as the GMPP head. Actually the heads feature 2.25 intake, 1.88 exhaust. I'm not sure but since you have a small bore engine those big valves may be to shrouded and limit there potential.Check out this site as it is the cheapest that I've found these heads. http://www.sallee-chevrolet.com/sales.html

I have EDELBROCK Performer RPM aluminum heads on my 396 whick are VERY similar to the GM heads. I milled the heads .035 to get the CC's down to 106CC. That makes for around 9.75 to one with my TRW forged pistons that have a very small dome.

The engine makes great power and because the heads are aluminum and dissipate heat better, I can run 150 shot NITROUS without having to retard the timing.

I think you would be happy with your combo. I would definitely have the heads CC'ed before putiing them on however. Mine were actually 112cc instead of the advertised 110cc.

[This message has been edited by sr71bb (edited 08-02-2000).]

The GMPP heads are available with both 2.19 or 2.25 intake valves. The Oval ports have 290cc runners and were tested by one of the magazines. They have a better intake to exhaust ration than the edelbrock heads even though they are made by edelbrock. The edelbrock oval ports are more of a hybrid betweeen a rectangular and round port. They have very good flow numbers. They are comparable to unported 990 iron rectangle port heads. I would get the smaller valves for a 396 depending on your cam and desired RPM range that you plan on operating at. A little minor port work would really make these flow well for a street car. I am looking into the same heads for my 427, but they are not my top priority.

Kent
67 SS 427

I forgot something. The magazine that did the test cc'd the GMPP heads and they came out at 112cc.

Kent
67 SS 427

Please show me were it states that these heads are available with 2.19" intake valves, as I've been following this head closely and have seen no such thing. Also I do have the CHP that tested these heads, so if you want to know the flow #'s or comparison to others let me know.

[This message has been edited by MarkM (edited 08-02-2000).]

Mark,

I looked in my GMPP catalog and on the Sallee chevy version that I downloaded and here is the information.

The casting number for the oval is 12363391. It has 290 CC runners. Semi-Open 110cc chambers.
PN 12363399 2.19I 1.88E No Valves.
PN 12363392 2.19I 1.88E Complete head. PN 12363390 2.25I 1.88E Complete Head.

The casting number for the square is 12363401. It has 315 CC runners. Open 118cc chambers.
PN 12363408 2.19I 1.88E Complete Head. Replacement for RPOL88
PN 12363410 2.19I 1.88E No Valves
PN 12363400 2.25I 1.88E Complete Head

Kent

Since I have a closed chamber piston, I can't run closed chamber heads? My pistons are not open chamber. How about running a 110 cc aluminum head from GM Performance Parts, I believe it is called the "signature series." I believe this to be my best bet, as I can buy a set for $1600. They come with 2.19" intake valves and 1.88" exhaust valves. They've got a great chamber design and look great, plus they would raise my compression. Anyone have any suggestions or imput to this head combination?

I am using 110 cc aluminum head. I bought it to a friend of mine. I can refer you if you are interested. :yes:

The oval ones work for me!However i felt they needed a "little " porting for my 525 and are now 330cc runners,with unshrouded chambers and then milled .100 to bring them back to 110cc for compression reasons.They work as good as the brodix -2s that were also ported that i had on this same motor years ago.Great heads for a 396 that you can "grow" with if you go more agressive or bigger in the future.

SRP makes pistons specifically for those heads and others may as well - they supposedly don't work with conventional domes.

Have you looked at open chamber heads that have been milled? Believe you can get AFR's new oval port milled to 114 cc. While you will loose compression, the flow numbers are significantly higher than GM's and probably would make more power. You could then upgrade pistons with next rebuild.