Longer pushrods can increase valve lift
Posted: Fri Dec 23, 2005 8:54 am
Hey guys, I saw this little article in December's HotRod Mag and found it quite interesting. I guess many of you know this already, but I didn't.
"setting the valvetrain up with correct geometery yields the most lift. But because about 80 percent of nonprofessionally assembled engines have a pushrod that's too short to achieve optimum geometery (primarily because most hot cams have reduced base circles that permit their fatter lobes to slide throught the fixed-id cam bearings)". Comp cams says "about a 0.100 inch-longer than stock pushrod is usually an improvement". To me this shines a new light on the importance of paying attention to correct valvetrain geometry when assembling an engine.
I wish I would have known this before I assembled my 460.
"setting the valvetrain up with correct geometery yields the most lift. But because about 80 percent of nonprofessionally assembled engines have a pushrod that's too short to achieve optimum geometery (primarily because most hot cams have reduced base circles that permit their fatter lobes to slide throught the fixed-id cam bearings)". Comp cams says "about a 0.100 inch-longer than stock pushrod is usually an improvement". To me this shines a new light on the importance of paying attention to correct valvetrain geometry when assembling an engine.
I wish I would have known this before I assembled my 460.