I have aluminum heads on my 1994 z28, I don't know what kind they are. How can i tell without taking them off? They are aftermarket, but don't have any documents to verify what they are...

 

How do you know they are aftermarket? Just curious.

 

Usually trickflow, AFR, and a few others will have names or symbols engraved on the heads.

-Dustin-

 

f-body and y-fbody LT1 heads are aluminum from the factory.. just fyi.

 

As Javier said these cars came with aluminum heads from the factory. If you pull the valvecovers you'll probably see the gm part number on them.

 

I am not an expert, but i did take the car to 2 experts and they should me a stock lt1 engine and heads. My were different as well as the water pump and injectors. You could see where the intake and heads where removed, the gaskets kinda overlay the heads and intake a bit. The car also smoked a 96 vette and ran neck and neck with a 2000 ws6 with 390 hp, he had the dyno sheet.

 

So the only way to tell is to remove the vavle covers

 

post a pic of this engine, maybe someone did an engine swap, if the water pump is diff from an lt1... either that or its an electric water pump. wheres the thermostat at? it should be on the water pump if its an lt1.