Yes, I did a search.

It's been a few years since I fooled with adjustable cam gears, and going through my notes, I can't find the section about adjustablility... on a SOHC, which way to make more top end power? Advance, right? I can't remember in my old age... Thanks guys!

 

Yup, advance it for more top end, retard it for low end. If you don't have access to a dyno to tune the cam gear, I've been told that 3+ degrees advanced works just fine. I wouldn't go any farther than that because you will then be dealing with clearance issues. Hope this helps.

 

If the cams are already properly indexed for maximum power over the rev range, retarding slightly improves the powerband up top while killing bottom end, and advancing does the opposite.

 

Thanks guys!

Texan- Cams? I have no need for two. I have boost. Anyway, I appreciate the input!

 

Doh! Yeah, I pretty much think in DOHC nowadays

The primary reason retarding hurts low end power is due to the intake valve closing event, where the low air column velocity causes excessive reversion and loss of VE. The exact opposite occurs at high RPM with advanced cams, where you can't take advantage of the high velocity to "ram charge" the cylinder after BDC, something only a late closing event can take advantage of.

 

Advancing gives you more low to mid power, retarding gives you more upper. Advancing 2 degrees on most SOHCs I've found increases HP through the whole range but 3 degrees starts killing top end. Retarded seems to kill bottom end regardless. Don't go more than 4 degrees either way or you might play the piston-valve clapping game, not good.