.030 over pistons

[randy73]

If I go .030, that should equal out to be about 3.5CI, right?

Thinking about a 340 here, been a looonnngggg time since I did the math and it is been bugging me, whether I did the math right or not.

Thanks

[XH29N0G]

I got the following

CI=8*stroke*PI*(Bore/2)*(Bore/2)
Stroke = 3.3125
Bore = 4.04 or 4.07
Pi = 3.14..
CI = 339.70 or 344.77

So about 5.07 CI increase

Someone will correct this if it is wrong.

[randy73]

Thanks, hate getting old, I have CRS bad!!

[Challenger340]

Don't forget also here in your Calcs... that a 4.070" Bore(.030" over 340) accounts for about 2.13 CC's(rounded) per .010" of Piston Compression Height(pin centerline to top of the Piston).
For example;
if the Flat Top Piston is .030" down from the deck at TDC... that is "3" X the ".010"(2.13 CC's) or 3 X 2.13 CC's = 6.39 CC's at .030" down the hole,
PLUS,
whatever the Piston Valve Relief Volume is.

[Kern Dog]

Oh yeah, THAT helps......