Subaru Enthusiasts Car Club of the Sierras - View Single Post - Shopping for a pre '02 Impreza, any advice??

Dean · 2009-08-04, 12:53 PM

In theory, as long as you can open/close valves when you want, number of cams is meaningless. In fact, more cams = more rotating mass and friction and possible miss timing between the cams even if only due to belt stretch.

2 cams more easily permits vvt and multi-valve intake/exhaust, but if you are not using those, then no real benefit.

Valve and spark plug position may be affected, which changes manifold flow, etc...

SOHC = KISS + cheaper.

2009-08-04, 12:53 PM	#6
Dean Señor Cheap Bastarde Real Name: Dean Join Date: May 2003 Location: $99 Tire Store Posts: 9,294 Car: $.04 STI Class: Fast,Cheap & Reliable=STI Deal, did somebody say Deal? Oh, Dean, yeah that's me.	In theory, as long as you can open/close valves when you want, number of cams is meaningless. In fact, more cams = more rotating mass and friction and possible miss timing between the cams even if only due to belt stretch. 2 cams more easily permits vvt and multi-valve intake/exhaust, but if you are not using those, then no real benefit. Valve and spark plug position may be affected, which changes manifold flow, etc... SOHC = KISS + cheaper. __________________ I am a Commodore PET --- Now get off my lawn you kids...