I've heard conflicting arguments on how much preload to set on retro-roller lifters. Mine are extremely noisey at 1/2 turn past zero lash. What ave you guys done.

 

1/2 turn on mine very quiet

 

The manufacturer states that retro-rollers perform their best with "at least one full turn". I'll give this a try.

 

I set them at 1/2 turn in always, never had a problem so far.

Be sure someone didnt sell you the anti-pump rollers. I just removed a set for the exact reason. The noise.

These run with no preload and do not act like a regular hydraulic roller.

Put a part number up here.

Harry P.Hunter

 

Don't know if all roller manufactures recomend a certain preload, but mine did. Crower recomended .030 to .060 plunger preload for their hydraulic rollers. First I found zero lash by snugging up a .002 feeler gage between the valve tip & rocker. Then set a dial indicator on the rocker tip. Tightened the nut down till it read .045 (in the middle) of travel, which was 5/8th of a turn, then locked it down. I set em all at 5/8 turn and my valve train is quiet as a church mouse.
Eddie

 

Comp cams part# 853-16


I'm not sure what the deal is, but even at almost 1 full turn, my valvetrain is nearly as noisy as my 2 kids.
I'm stumped.

 

That is the right lifter for street use. I use many and have not had a single noisy lifter.

The ones you dont want are the 885-16's the pro-magnum series for the street.

Harry P.Hunter

 

Sorry, I can't agree. I'm running Pro Magnum rollers (875-16) & have no valve train noise. The preload was set to Comp's specs (somewhere around 1/2 to 3/4 turn after pushrod contact).

sperkins - How did you determine zero lash?

 

HP Hunter is talking about the Pro Magnum Lifters............................ I think.
You are talking about the Pro Magnum Rockers................................ I think.
Those 1.6's worked out pretty good for your build I see.

 

1. I let all lifters return to a neutral position by removing all rocker arms and pushrods overnight. I wanted to make sure I didn't have a bent pushrod due to overadjusted valves and pop up pistons.

2. Re-installed everything and found zero lash by twisting pushrod until resistance felt.

3. Marked the poly locks with white-out to make sure all valves were adjusted the same.

4. Adjusted all valves to "almost" one full turn per manufacturer recommendation.

 

Rockers & lifters are both are Pro Mags. Yeah, those 1.6s you sold me are the cat's meow.

I also have a Hydra-Rev backing up the lifters.

 

One thing I don't see, did you rotate the engine so that you were adjusting each lifter/pushrod while it was on the base circle of the cam?

 

I got a Hydra-rev for my setup too. Waiting for my turn on the dyno! Numbers coming soon!

 

Yep. I adjusted the intake rocker as soon as the exhaust started to open, and adjusted the exhaust when the intake after full lift and was 2/3rds closed.

Now that I've checked again, I think it's actually the rocker arms I'm hearing. That's weird because they're Crane full rollers?

 

When you feel the pushrods now, are any loose?

 

[QUOTE=ratflinger;1562024984]Sorry, I can't agree. I'm running Pro Magnum rollers (875-16) & have no valve train noise. The preload was set to Comp's specs (somewhere around 1/2 to 3/4 turn after pushrod contact).

ratflinger, not sure where youre getting the preload from for the 875-16's but Comp Cams recommends .002" to .004" preload.

This are the anti-pump lifters that are required for cars running a very specific NHRA class where they originally came with hydraulic rollers.

The specs for adjusting them are here in the catalog. The difference in the number youre using and the 875's is yours are for the factory roller blocks. Any Pro-magnum lifters are not recommended for street cars, they let the motors get higher up in the RPM band without valve float. The idea is to stop any lifter pump-up with the hydraulics.

These are the same lifter design as the original anti-pump flat tappet ones except for the addition of the roller. They work the same!

Read the link here:
http://www.compcams.com/Technical/In.../COMP4-115.pdf

Harry P.Hunter

 

Harry is correct, I dug out my build records & 1/8 turn it is. However, according to Comp (via the chevelle forum) if you tighten them 1/4 to 1/2 all that happens is that you lose 200 - 300 rpms on top.


sperkins - how much of the lock nut is down on the shaft? gofast stated over there that they had seen (heard) rocker arms making the same clatter as lifters if the nut was too high on the rocker stud, it was actually wiggling a little. AFR head's stock 3/8 rocker stud was too short for Pro Mag rockers. I see you have Edlebrock heads & I don't recognize the rockers, but maybe the same thing is happening with your combination.

 

As far as Pro Mag lifters not being for street use, here's a press release from comp:

COMP Cams® Pro Magnum™ Hydraulic Roller Lifters Increase Performance Of GM Vortec 350 & GM LT1 Engines

Pro Magnum™ Hydraulic Roller Lifters and Installation Kit provide the ultimate in hydraulic roller performance and durability

COMP Cams® Pro Magnum™ Hydraulic Roller Lifters feature state-of-the-art technology, making them the best choice when installing a high performance camshaft in GM Vortec 350 or GM LT1 engines. To further ease the installation process, COMP Cams® also offers a new Installation Kit which includes everything you need to properly install Pro Magnum™ Hydraulic Roller Lifters in GM Vortec 350 and LT1 engines

COMP Cams® Pro Magnum™ Hydraulic Roller Lifters are designed to perform at higher engine speeds and resist improper internal piston positioning (called pump up) that can happen when engine rpm increases. This improper piston location results in valves being open longer than required, thus leading to power loss and potential engine failure.

The new COMP Cams® Hydraulic Roller Lifter Installation Kit for '91-'02 GM Vortec 350 and '91-'97 GM LT1 engines includes everything you need to install your Pro Magnum™ Lifters, including eight lifter guides, one lifter retainer, one cam retainer, two retainer bolts and three cam bolts. Of particular interest to engine builders is the new cam retainer (Part #8104-CR) with 3.294-inch bolt spacing, which was specially designed for these two engine applications. Best of all, the kit ensures proper fit through the use of brand new parts that meet or exceed OE specifications, so the performance you expect is the performance you receive. For more information about COMP Cams® Pro Magnum™ Hydraulic Roller Lifters, the Hydraulic Roller Lifter Installation Kit for '91-'02 GM Vortec 350 and '91-'97 GM LT1 engines or any other COMP Cams® product, call us at 1-800-999-0853, or visit us online at www.compcams.com.


It is the 875 lifter they are referring to. The 885 is the same lifter except with a link bar.