Sup all.....I am almost finished on Port and polishing my heads (30 hours later) and I was told to also grind away the excess casting in the oil passages where the heads were molded. Does it really make that much of a difference in cooling and oil flow?

 

well, i dont think its gonna make a HUGE difference, but it can never hurt to take 1 hr and clean all that junk. I mean even if its just a little bit of help, its still help, and its not like you can ever get too much oil or coolant flow.