Heads

Aluminum verses cast the good and bad

Most people today just opt for aluminum, but I am favoring cast iron for street performance, (rightly or wrongly). There are arguments which can be made for either option.

what's your goal?

cast is cheaper and heavier. being OEM, you'll want to get some porting on it to help out power production.

modern alums will typically flow as much or more out of the box than you can get from a max porting effort from a professional out of cast irons. plus the weight savings, means with equivalent built engines, the alum headed combo is normally going to be quicker. if you pay for a full on porting effort, you're probably not going to save any money on the cast head.

alum rejects heat quicker than cast, so you'll probably need to shoot for an extra point of compression in the build over cast.

if you're trying to do all the work yourself and use as many stock parts as possible, i'd find the highest compression OEM pistons i could get my hands on, come up with a couple of spare cast heads and fool around with porting.

if you're going to replace the pistons and rods anyways, it's probably easier to just slap an alum heads and intake on top.