Is it reccomended to put aluminum heads on a cast iron block? I was told because of the change in temps that the heads wouldn't stay torxed? Is their any truth in that?

use good head gaskets Fel-Pro or Cometic. Do a heat cycle on the motor and re torque them. You will be good to go.

Just remember that you are building an engine with dissimilar metals. Add salt water and you have a battery. If you are running the engine in a fresh water environment it won't be such a problem. Consider a closed cooling system to avoid electrolysis.

Also, keep in mind that some of these aluminum head manufacturers have what is called "hard anodizing" available as an option where the water jackets and other areas are coated with a material that prevents corrosion---especially in salt water conditions.

Yea, Pretty much I'm trying to decide on the Edelbrock oval port Aluminum heads for added performance or the Dart Cast Iron heads for reliability. Edelbrock comes hard coat anodized which is cool. I'm leaning toward the Edelbrock but just want to make sure its the best choice.

I had some problems initially this year with my aluminum heads. But when the Fel-Pro gaskets were used, it solved the problem.

I've had the Edelbrock aluminum heads on my ZZ502 for four seasons now, and not a problem. In fact they're gonna get replaced with another set of aluminum heads over the winter .... AFR's

Not a problem with head gaskets designed for the job.

I don't know if I would trust hard anodizing for protection in salt water. Any defect in the anodizing, and you may have a hole there.

Michael

I know a marine mechanic that ran aluminum heads on his engine exclusively in salt water. He took them off seven years later and sold the heads. It's all in the flushing.

Or you could paint the inside of the heads YELLA,,,,,,,,,,,,,