1DOHC or Double OverHead Cam - the setup used in many today's cars. Since it'
s possible to install multiple valves per cylinder and place intake valves
on the opposite side from exhaust vales, DOHC engine can "breath" better
meaning that it can produce more horsepowers with smaller engine volume.
Compare: The 3.5-liter V6 DOHC engine of 2003 Nissan Pathfinder has 240 h.p,
similar to 245 h.p of the 5.9-liter V8 OHV engine of 2003 Dodge Durango.
Pros: High efficiency, possible to install multiple