Hi i hope i can ask here.... my Name is Sven and i write from Germany. I have a Question. I drive a 1960 Pontiac 389 2bl. I need a little more Power and i buy two 1964 HO Heads with Intake and 4bl Carter Carb. Will fit this 64 Heads without Problems on my 60 ? Thanks a lot and sorry for my bad english
Hello Sven, The '64 heads will fit the '60 block. You must use the '61 -'64 intake that is compatible with the intake port and water port design of the '64 heads. However you will need to plug the thermostat byp*** p***age at the very front of the intake since the '60 timing cover has no provisions for sealing the byp***, simply tap it for the appropriate size pipe plug which will be either 1/4 or 3/8 NPT. You will also need the '64 rockers and pushrods as well, the 1960 pieces are not the same. A question on your '64 heads, what is the casting number on the two center exhaust ports? If they are '64 HO heads then they will have casting # 9770716 on the center exhaust ports. '63 -'64 421 HO head casting # 9770716 was shared with the '64 GTO 389 for that year . These big-valve (1.92"/1.66") heads were the best Pontiac production p***enger car heads available at the time. The standard '64 389/421 heads only had 1.88"/1.60" valves, the same size valves as your current 1960 389 heads. Good luck, Bart
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