Re: How much cam for a 265 SBC Gen 1?
assuming this is a class stocker...the original '55 and '56 265 pistons do not have valve reliefs. the pistons are flat. however, if you are going to an overbore, you will not find 'replacement' pistons which do not have four reliefs. real race pistons can be had with only two reliefs.
'55 and '56 heads had the plug way back in a notch, the chambers were small, but the valves were further away from the piston at TDC, than later model heads. power pac heads had a a smaller CC chamber than the 2V heads, which raised the compression. stock class cams had less than .400" intake lift. you will not have any problems with a true flat top piston.
if this is NOT a class legal car, and you have notched pistons, you can run a fair amount of lift .480 or more, as long as you stay with the 1.75" intake. with a 60 overbore and a deep notch you can run a .570 lift with a 1.94" intake. a 1.6" exhaust valve will also clear the bore. however a 2.02" intake will hit the bore with anything more that a .500" in a 462/492 style head.
put your cyl. head on the block with the piston at TDC, pull the spring off the intake and drop the valve down and use a caliper to get a close measurement.
rod in AZ
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