A buddy of mine was asking when you bore 030.,060. ext.ext. what size does that make engine in cubic inches? Like say 460cid. or 351cid would like to settle a dispute (friendly LOL). were just talking boring now and not stroking or head work. Thanks.








PSYCHO 1977 F-250 4x4 472cid race truck,PSYCHO2 19771/2 F-250 4x4 472cid and goodies to go with it!!!,1987 Mustang GT 5.0 H.O. SNAKEY2. 1988 Mustang LX 5.0 H.O. Spectator Eliminator!
Not worried about gas mileage just performance!!!

 

i dont know the exact formula, but on the destop dyno, if i add .060 to the bore of my 460, it comes out to be 473ci

 

Here goes: CID = cubic inch displacement. Figure out individual cylinder displacement and multiply by # of cylinders. For example: my six cylinder is 300 CID. How is this arrived? area x stroke x number of cylinders so: area of a circle = pi(r)squared... 3.14 x (2)squared (4) = 6.28...x stroke length (3.98 - in my case) = ~25 X 6 cylinders is 300 inches cubed.

Like wise a 351 is the same bore 4" the radius is 2". Pi(r)squared is 6.28 again...since the number of cylinders is eight, the stroke length would have to be 3.49" to equal a 351...hence a 400 is a 351 stroked to 3.98" which makes sense comparing a 6-300 to a 8-400.

To bring this one step further, a 351 bored .030" over will have a radius increased by .015" ...so... 3.14 x (2.015)squared = 12.76 x 3.49 = 44.52 x eight cylinders = 356.1 CID.

Good Luck!

 

the auto math handbook that you can get from si\ummit or most lager book stores is a great resource for most anythig you can think of.