Compression: An automotive term used by everybody, forever. Let's get into some detail and maybe develop a better understanding. Pressure, and more pressure: It's a must-have to produce power within ...

starts with the piston at the top of the cylinder (TDC) and the intake valve open to admit air and fuel. At bottom-dead-center (BDC) the inlet valve is closed and the compression stroke (b) starts.

You may have heard your car has a four-stroke engine, but you're not sure what that means. Why are there four? And what is a stroke, anyway? A modern gas engine most commonly uses pistons and a ...

Wait! Don't say anything. Okay—they're gone. I didn't want those guys to hear what we were saying about them. Who? The people who flipped past this article without reading it, of course! You see, ...