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Old 02-08-2022, 11:56 PM
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Tom Vaught Tom Vaught is offline
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Join Date: Dec 2001
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Quote:
Originally Posted by FrankieT/A View Post

Ram Air 4 cam Factory Ram Air 4 lifters (Try and find those today)
If you have never taken the RA-IV Lifters apart, if you do, you will notice that the pushrod cup that is
retained inside the lifter is actually different from a normal lifter in height (if you sit them side by side on the bench).
(the bottom of the RA-IV lifter Pushrod Cup is thicker vs a normal lifter). The part is taller.

This makes them a "Limited Travel" lifter which helps with them not "pumping up" at high rpm and hanging a valve open.

Many times the special Pushrod cups can be swapped to several lifters sets over time if you were trying different
camshafts at the race track.

RA-IV grinds but with different advance/retard profiles.

I wish Johnson or someone would build some of those pushrod cups again.
Then you could use the cups in other lifter sets from Johnson.

Tom V.

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