Bored & Stroked

[PKRWUD]

To figure an engine's displacement, the formula is:

pi / 4 x bore squared x stroke x # of cylinders

Now, pi (3.1415927) divided by 4 equals .7853982, so the first part of the formula will always be .7853982:

.7853982 x bore squared x stroke x # of cylinders

Now, a 302 has a 4" bore, a 3" stroke, and 8 cylinders, so, by substituting those numbers, you get:

.7853982 x 4 squared (16) x 3 x 8 or:

.7853982 x 16 x 3 x 8 = 301.5929 cubic inches

With me so far?

Okay, now let's say you bore the engine .030" over, which means increasing the bore diameter of each cylinder to 4.030". Then the formula would look like this:

.7853982 x 16.2409 x 3 x 8 = 306.13375 cubic inches.

If you were to bore it .060" over, the formula would become:

.7853982 x 16.4836 x 3 x 8 = 310.70853 cubic inches

Get it?

Take care,
-Chris