Better heads

67,
Once again it's build dependant for head choice. For a given 318 .030 with KB167 pistons I would use a 302 head with 136 cc's of intake port volume and 225-235 cfm's and this is achievable with a 1.78 intake valve. Just like I just flowed a head for another customer and the exh. flowed over 200 cfm's with a 1.50 valve.

As for a 318/349 combo I would use something like 155 - 160 cc's of intake port volume with a 1.88 and a 1.60 valves that should flow in the 240-260 range and the exh. should go in the 180-210 range. But as I've said before it really depends on the cam and compression that the engine will end up with. This is why it's very build dependant as to modifications done to the heads. I hope I'm not being too vauge but every engine is different, just as machininst's are and the equipment that they use. But good quality should still be good quality reguardless of what it is or how it's done.