I had a slight knock from the engine at 180k miles. Google this and found Piston slap was common to this engine. Im ready to pull the engine and thought about the intake that I had replaced the gasket on at 40k miles and wondered if that may have gone away. Yup it did. coolant in the oil.

Heres my question. Would it be better to swap out my aluminum heads with Iron heads?. The Aluminum heads look to be corroded good at the water passages. Use NApa intake gasket rather than the Plastic stock gaskets.

I have a set of Iron heads I picked up with another R vin motor that has a bad crank. #1 and #2 rod bearings on the crank on this engine are toast. The crank is toast too. So I have an extra block to build. Just wondering about the heads for now.

 

Those Alum Heads can certainly be cleaned up nicely, but...
do you know what difference between them in the compression ratio or Valve sizes. Could be a good opportunity to add a little "punch" to your engine.