cam regrind...what exactly is it?

[Canada]

So, what exactly does a cam regrind include? How is it machined? Everyone throws this term around.....but....I don't know what it is, other than it isn't as good as 'normal' aftermarket cam.

[geoffinbc]

They simply regrind the cam. Taking material off in certian areas to change the profile.

For instance if you took material off the base circle of the cam well then the lift would increase. It does this because you lowered the "zero" point so now the difference between that and the top of the lobe now increases. Thus increasing overall lift.

[StudlyCamaro]

they take a stock cam, and re grind the lobes to different specs... when they do this they make the base circle of the cam smaller and thus the valvetrain geometry is different than stock, which can result in problems

[Canada]

I dont follow......

By grinding 'zero' lower.....how does this make more lift? Sure the difference is more....but the max lift is the same. How do they compensate? Longer pushrods? Valve stems?

[robby1870]

yeah, custom pushrods are usually needed with a regrind, since the valvetrain geometry is different. Like they said, the base circle is lower, so the lifter is farther down in the block when the valve is closed (cam at base circle), so a custom lenght pushrod is needed to keep stock geometry. Since the lifter is farther down in the block, the overall lift of the cam (lobe height minus base circle height, basically) is greater, meaning more overall lift. HTH

[Anonymous]

Think about it this way... if Lift = Lobe - Base, then reducing Base increases Lift.

[Canada]

Oh I understand the fact that if yu lower the base, then you get more lift.....I just didn't know what exactly was involved from there to get the proper valve train geometery.