250 bore

The reason I'm asking about the cylinder bore diameter is, I found a set of pistons that will work with my build that are 3.80 dia. aussi7mains helped me eliminate those pistons. I also found another set that are 3.691 dia that will fit the build.
My build will be those pistons, 300 rods, 3.91 stroke. The head is an E0 head with 3 740 webers. The cam will be a .515 lift 280 duration 110 LSA. I am getting ready to retire and am going to build this engine. I have 4 more heads and plan to build a 2 carburetor head, and independent runner intake for these 3 carburetors. My goal is 250 to 300 horsepower.....
 
Compression height
The distance from the center of the wrist pin to the top of the piston, technically it might be to the top of the compression ring. It will change how far up your piston will be at tdc
 
an alternate 250 Piston in my '61 is AMC/IHC 4.2/258 (TRW/SealedPower # 470NP std) Pistons require an .070 over bore to 3.75" .
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The trick pony' of these pistons is the CH raises piston height .133 about where stock pistons are down from deck similar amount -
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AND specs list the pin diameter of the ford at .9122 and the AMC's at .9310 which can easily be accommodated.

from the wayback machine:
"The AMC Pistons depression is much bigger than a 200/250 piston , 2 to 3 times the volume. CR lessened significantly and still maintain zero or negative deck height with the .133 additional compression distance"
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hav e fun
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250/258 will launch at 5500 and still has drivable low RPM grunt ...
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