Using the 3 valve head is much easier. I can get navara 3 valve heads. Wanted to kno also what my compression ratio will be if I use a stock ka24e head on a stock series 2 bluebird (910) bottom end? I dont think it will make the 10-10.5:1 compression ratio I wanted. Can I use any other piston or rod and piston combination? Im getting into not so familiar territory but hey this is what its all about isn't it?