273 Build

66fs said

Thanks, I'm not asking you to do more work. Just asking which heads you were talking about.

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I think there are more differences in 360 castings then 273/318. 360 intake port volumes varied, exhaust port changed 5 times at least. 915,587 air injection , 974 air injection boss raised higher, then the 308 head ex port and return to 915 I take port etc.

318/273, they changed the chamber 3 times, closed, open, closed with a sharp point...ping ping.. jk.
Ports maybe changed once, imo..the early intake is more squarish across the short turn and that's more than likely cruder casting. That's all I noticed, and they still flow the same. Exhaust port got air injection bosses too..except that hurt the 318 because the floor was already raised.