dr97z

Has anyone ever had issues with Comp Pro Mag 1.6 rockers. I was having some issues with them coming loose at first, when I went in and re-lashed, I noticed theirs a metal powder coming out around the trunion. AFR said they don't like the Pro Mags, because they claim weight savings, but they don't think they do. They said they tend to bounce around at high RPM's and recommend switching to an aluminum rocker for my setup. They also said the cam is very agressive on the valve train, so keep this in mind. The thing pulls nice and clean on the dyno up to 6500 then seems like a missfire, maybe floating valves, but valve springs are plenty for application, could the rockers be causing this. At 6500, I have not peaked out yet.

wrd1972

The pro-mags do weigh more than aluminum rockers so yes they will float valves more easily and at a lower RPM than aluminum rockers because of funamental physics. Also they tend to make more clicking noises than aluminum rockers.

Stl94LT1

Overall the Pro Mag's weigh more than Al rockers. But, Comp claims the weight over the valve is less.

wrd1972

I think that statement by Comp is smoke and mirrors and marketing. If the thing weighs more, laws of inertia still exist.

1989TransAm

"I think that statement by Comp is smoke and mirrors and marketing. If the thing weighs more, laws of inertia still exist. "

Interesting that Comp brought out a new line of aluminum rocker arms last year. I have also heard the same thing about the Pro-Mags and that is why I'm going with aluminum rocker arms.

Sounds like you are running into valve float. If you are getting powdered metal from the rocker arm it needs to be replaced. You don't need metal floating around in the oil and a rocker arm on the verge of failure.

evilundisguised

I can't confirm or deny Comp's claims, but there is a difference between overall weight and moment of inertia. Mass has more effect on inertia the further you get from the axis of rotation, so the "weight over the valve" statement could be more significant than total weight.

dr97z

cam calls for installed height of 1.750 = 100 on seat, which I've talked to Lloyd about it and he says no way.

I'm using AFR 8019's installed height of 1.800 - 1.810 = 155 on seat. All, Lunati, AFR, and Lloyd all say that should be good.

The only thing I see as a problem is metal coming from rocker arm and AFR's statement about pro mags.

shoebox

If you have a bad rocker, then by all means, you should get it repaired. You preload setting can affect valve float.

There are an awful lot of people running Pro Mags that don't complain about float.

1989TransAm

"There are an awful lot of people running Pro Mags that don't complain about float."

I agree. But than again how many rpms are they turning. It could be subtle and they may not know it is happening in the higher rpms unless on a dyno. In this case we are talking 6500rpm.

Injuneer

My Pro-Mags were installed with the stroker build in 2000. The engine has a 7,200rpm redline and runs all the way to 7,000rpm shift points on nitrous. Running a mild solid roller cam. I've never had any problems with them. It was a daily driver for aobut 2 years, but since then have had very limited track time and a bit of local driving.

ACE1252

Isn't that a spring problem instead of a rocker problem?

1989TransAm

Not necessarily. Valve train weight will also cause valve float.

shoebox

I obviously don't know how many RPM they are turning. I was just pointing out that so many people are running them, that chances of the problem being the rocker is not logical (IMHO). You have to figure that a lot of these are race engines and see plenty of high RPM. As Fred/Injuneer indicated, his properly set up valvetrain with Pro Mags has no issues.

With the way the internet community is, if there was an issue with Pro Mags, everyone would be avoiding them like the plague.

dr97z

So even if it's not a weight issue, something could be going on in the rocker for it to be wearing enough to have have that metal powder around the trunion, right. I just don't know what would be doing this. These rockers were on my last motor that I had numerous valvetrain issues on (which I didn't set up myself)

shoebox

You need to dissect the rocker(s) to see what the issue is. Maybe oiling or ?? Comp can rebuild them for you.