Aluminum Heads

[TTipe]

I have a new shortblock (Diamond pistons 0.005 below the deck 29.5 cc dish volume) and Champion aluminum heads (46 cc chambers ,1.90 int,1.60 exh valves).I would like to use a 0.027 head gasket (Cometic) thickness which takes me to 8.74 :1. Do I need to clay a piston and verify a required clearance? Does someone have experience with Cometics and Champion aluminum heads? Does someone know what kind of pushrod angle is created when using Champs,a hydraulic roller with Morels and a stock rocker on a heavy duty shaft. I'm thinking that the side loads created are just asking for a failure. Any help is appreciated.

 

[earlbrown]

You should always clay a piston. I've got .060 from the head with a 215/220 and it clears the piston.

I also lowered my rocker shaft .025 (I think) to get better vavletrain geometry with stock rockers.

 

[PSID6]

I'm not sure what your concerns about champion aluminum heads are? They are a stock replacement cylinder head which uses the stock valvetrain. As far as checking piston to valve, It is always a good idea to check with Clay or a dial indicator and checking spring. But most likely a dished piston and a mild hydraulic cam you should have plenty of piston valve clearance. Unless you changed the lifter bore angle and angle milled the cylinder heads you are not changing the dimensions from stock.