Any info on these lifters would be appreciated.

What is the theory behind the bleed down at low RPM?
What are the pros and cons of this lifter?
Are they noisey?

Thanks
Paul

I had them in a past car. The idea is that they bleed down at idle for less lift. Pretty good theory. I think that it would only be needed on a real radical cam. Of course, everybody is running rollers today and they don't offer a hydraulic roller like that. Never knew why though...Anyways, they wern't real noisy. Just a slight tick.

My dad had a pair laying around from years ago. So we put them in a 454 we built.

454 .125 over
gm rect heads
merc 420 cam
rhodes lifters
12:1 comp

480hp/540tq

We don't have much time on the engine but seem to run really good!!

i had them in a street car years ago. nothing but problems out of mine. they got swapped out i believe in under a month.

Thanks for the input. I am looking at a boat that has these lifters in a warmed over 454 Mag. I never heard of them before and was curious.

They are kinda old school. Were made for cars running big cams (low or little idle vacuum) that used vacuum for other control things and these gave better vacuum at idle.

Hmmmm. It sounds as though these lifters are obsolete.
Wonder why an engine builder would use these on an engine upgrade 3yrs ago? Question is to leave them in and run them or replace. I am afraid of lifter failure leading to something more catastrophic. Any opinions?

Rhoads Lifters are still produced.

The way I understand, it is actually just the opposite. Bleed down at low RPM does not allow full realization of cam profile. When oil pressure is increased, lifter pumps up all the way to get full affect of cam profile.

After further research I am comfortable with these lifters.
Case closed.

Thanks
Paul