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Old 06-19-2008, 09:27 PM
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BrianHynes BrianHynes is offline
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Join Date: Dec 2007
Location: Northern New York
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Quote:
Originally Posted by Shifty View Post
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.
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