DETROIT -- A key factor in General Motors' ability to play an aggressive price game often goes unnoticed or even draws criticism - GM's heavy use of pushrod engines. Performance buffs belittle ...

Overhead cams are a more efficient method of actuating the valves than with a pushrod, but someone in Detroit never got the memo. And thank goodness they didn't. With production pushrod mills turning ...

Last month's "How It Works" story gave you the basics of the four-stroke cycle, describing the motion of the intake and exhaust valves in relation to the piston moving up and down in the cylinder.

General Motors plans to use the largest displacement engines possible to cope with the increasing weight of vehicles and consumers' thirst for more performance. But more cubic inches under the hood ...