Need help with cam selection...

[BrianHynes]

Originally Posted by Shifty

I know the rollers aren't too much of a gain...

This couldn't be further from the truth. #1 -- you gain longevity, and dependability. #2 -- there is most deffinitely a gain in performance. If you picture a flat tappet lobe, it is shaped like an egg. This makes it's max lift/duration very brief, and it is a difficult curve for a flat tappet lifter to follow (valve float). A roller on the other hand has more of a square profile. this accelerates ramp speed, and get's the valve open much faster. Once at max lift, the lifter remains there for a longer duration. This amounts to a wider fuel/air window a more torque. A roller will bring on the torque sooner, and longer than the same lift/duration flat tappet. A roller is quite a bit more costly than a flat tappet, but requires no brake in period, is dependable, and deliver much better performance.