I have the comp 1321-16 pro magnum rockers on a 493 street strip engine and noticed that the stamped rocker hold downs are wearing away. When I built the engine the rocker arm side clearances were set to .035" and comp recommends a minimum of .030" I first noticed it when I bent a couple pushrods the side clearances opened up to .045-.050" and were set to around.040" The motor has 500+ miles on it now the top end or has a slight tick so I went to reset the preload on all of the lifters and noticed that the side clearance had opened to .060-.070" plus on some rockers. whats acceptable? I noticed that hughes makes billet hold downs and shims and was wondering if any one knows if their hold downs would work with the comp rockers I would think they would. I plan on calling them monday. I am curious if anyone else has had this problem or has heard of it or has any advice.

Thanks, Cody

Heres a picture

put a .030 shim on each side and grind your clearance on the hold down.

I know lots of engines are built with the Comp stamped retainers and work OK. I wanted something a little more robust - with more contact area on the sides - and went with the MP aluminum hold downs. I believe the Hughes (steel) are good also.

With either of these some extra fitting may be needed. On mine, the rockers lacked clearance. I had the sides of the holddowns milled to reduce width and used shims to set position and clearance for the rockers.

In your case, I think I might do as the poster above suggets and add shims. They will take out the extra clearance and provide a better wear surface... but an upgrade to the more robust hold downs wouldn't hurt.

Here is a picture of the Hughes. They did have to be machined for clearance.

Thanks for the replies. Hemi allstate thanks for the picture I am curious if you are running bushings or running them how they came from comp? I am thinking about making some of my own hold downs out of chromoly tubing and making them work with some .015 shims or try grinding the spacers down and running the shims like performance only said.

Those rockers are not bushed, and it has a fairly mild hydraulic FT cam. Also, I have yet to install and run the engine.
Mark

everyone has opinions mine is that i would not use those stamped hold downs with anything but a basic stock cam and rocker type engine. i don't feel they properly clamp the shaft plus the potential problem you're seeing. the hold downs and spacers on this engine came from huges and i did (expected to) have to trim them some. i also would not use bolts in aluminum heads, these are ARP studs. not the best pic but this is the way i set up the crane rockers on the mild 383 i'm putting together, i also never cared for the springs between the rockers.

Thanks for the info jamesc. When I got the rockers off I noticed that there was a hot spot on the rockers and the shaft was missing some of its finish. I talked to RAS today and I am thinking about just getting the hughes hold down and stud kit and machine them to work. I was also recommended to banana groove the shafts for some more oil flow which probably should have been done the first time but I have seen people running them at much higher spring loads. So hopefully no more problems when I get it back together.

i know people often restrict oil to the valve gear but personally i don't like the idea i've just seen too many burned up valve train parts. i like to groove the fourth cam journal then install .060" orifices in the heads. i prefer full time oiling over the hit and miss of the factory setup. i've never worked with the comp rockers, they look like a nice rocker but that's steel on steel and without oil it's a problem waiting to happen. i assume the shafts are the ones sold with/for the set and that they are thicker and/or of a better material. poor shaft quality, uneven clamping (stamped hold downs), over tightening can all distort the shaft and cause the rocker to bind which will gall it real fast. i think the banana grooves are a good idea i added them to the shafts on the engine in the pic. if they already have some damage make sure it's cleaned up proper (parts replaced if necessary) and receive adequate oiling or it will happen again.

Well heres a picture of the shafts with the new banana groove. Now I am just waiting on the hold downs then machine them and I should be ready to go