Noisy Hydraulic roller lifters
 

There has been a lot of complaints about noisy hydraulic roller lifters. We've been round and round with this ourselves with a 326 we put a roller cam in. They were Morel lifters, sold by Lunati. We called the owner of Morel after the first set was noisy, and he agreed to make us another set. We installed them, and just like the previous lifters, they were quiet for the first minute or two, then they started getting noisy again. After 2 minutes, they were noisy as can be. I have been saying right from the start that the problem is with the placement of the oil band. It is too low, and at the base circle, it drops out of the oil hole, so no oil pressure is present while on the base circle, so no oil to refill the lifters at the critical time when they need the oil. After all, the lifter can't refill while under pressure from the springs.

So the apparent fix is to elongate the oil hole in the block to extend it down another 1/4" so it is open to the lifters oil band while on the base circle. Obviously this is not an option for the assembled engines with this problem. So what we did was cut a groove in the lifter body to extend it up about .150" so it can see the oil hole while on the base circle. Here is a pic of the modification. I will post when I get the affirmation that it fixed the problem for sure.

We have had two lifter manufacturers tell us that they use Chevy lifter bodies for the Pontiac lifters because they don't want to tool up to make a specific lifter for a "limited market", according to them. Well, maybe, just maybe, if they made the parts right in the first place, more people would buy them. But with the current complaints of noisy lifters, people are gun shy of using them. They tell us 90% of all noisy lifter complaints they get are from Pontiac owners. WELL, MAYBE THAT'S BECAUSE THEY DON'T MAKE THEM RIGHT! Did they ever think of that?

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Cool!! If this works, you will be a very busy man!

All of the negative talk about hydraulic roller lifters is why I put Crower solid rollers on my Stump Puller cam from SD Performance. Hope this fix works out for you and it becomes common on new roller cam builds.

I'm still not convinced that putting solids rollers on hyd. roller cams is the right thing to do. I wonder if that is why the PRW rockers were having troubles. I have used several sets of PRW rockers without a single issue. But then again, I'm running hydraulic lifters on hydraulic cams. This customer was willing to try the hybrid system, but we have been warned against it by Harold Brookshire, so we want to make it work with the right components. Not willing to take the chance with a customers engine.

What he said^^^. I have a nice Hyd roller that ran very well that I may go back to. I also went to SR lifters, but prefer to have some quiet HR lifters on it.

Thanks for your Insight, Experience , & pictures shared GTOFREEK.

Do the CC HR lifters have the oil groove in the right place? I have a set of the original 857-16's in mine with about 20 miles on them that just started clacking!

Nobodies HR lifters have the oil band in the right place. They all use Chevy lifter bodies. I have a 455 at work right now that has Comp HR lifters. One of them has the axle coming out, and hurt the cam. I have to rebuild the engine now. Those lifters have the same, low oil band.

Interesting thread. Attached is a Morel lifter (left) and a Comp 857 (right) non "S".

Paul,I have a set sitting on my shelf ready to put in my engine.Will compare with my Isky solids.I can tell you the last 3 engines have the new comps with NO issues.Tom

And the Morel still isn't high enough.

I have a set of Crower Hydraulic Rollers ready to go into a 455. Had the early version Comp Rollers in before. Taken out for the noise. Won't be happy if these are noisy. Anyone know who makes these for Crower?

Do the Crower look like the Comps I posted a picture of? ;)

Here's the Crowers.....

Pontiac HRs from Lunati (left) and CompCams (right) from 2 projects about 3 years ago.

No noise complaints from either owner.


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Base Circle
 

You may find that the Base Circle on the Camshaft was Ground Improperly. Too Small to be clear.
That would cause the Lifter to drop down out of the Lifter Bore Excessively while Riding on the Cams Base Circle.

With a Custom Cam Grind, this can be Dictated, to a Degree, by the Purchaser.

Larry S.

Isky solids,and comp new hyd roller.Tom

Johnson short travel hr's

I was under the impression that the Crower Hydraulic Rollers were Johnson.
Crazy buying these and not knowing what you're actually getting. How many manufacturers are actually making hydraulic rollers for pontiac?

The Johnson's are also Chevy lifters retrofitted?