Thread: My Prozac

Tweet

realitycheck, all of us started where you are today, not knowing much of anything about motors or cars in general. I think I'd be safe in saying that most of us learned the basics from reading, then asking questions about what we didn't understand.

I'll try to help get you started:
The small block Chevy (SB), (SBC), is called that to differentiate it from its larger brother, the big block Chevy (BB), (BBC). The small block is smaller in the physical size of the motor as well as the internal displacement. Small blocks which look similar on the outside through the years have been the 262, 265, 267, 283, 302, 307, 327, 350 and 400. These numbers indicate the internal displacement or "cubic inches of displacement". To find the size of the motor, you would need the bore size (diameter of any one cylinder) and the stroke length (distance that any one piston travels in its bore from top to bottom). In the case of the 350, the stock bore is 4.000" and the stock stroke is 3.480". If you multiply the constant .7854 times 4.000 times 4.000 again, times 3.480 times 8 (the number of cylinders in the motor), you get 349.84 cubic inches, which rounded off, becomes 350.

Here is a chart of engines showing the bore and stroke so you can get accustomed to how different engines use different combinations....
http://users.erols.com/srweiss/tablersn.htm

Let's say for instance that the motor you're getting is a stock bore and stroke motor, but it has quite a few miles on it and the rings are worn out and the cylinders are tapered and egg-shaped (very normal to find on a tear-down). You may want to bore the cylinders to the next oversize and use new oversize pistons and rings. The most popular first overbore for a 350 is 0.030" (thirty thousandths of an inch), so your motor would measure 4.030" bore and 3.480" stroke. (355.11 rounded off to 355 cubic inches)