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Another good option and I ran those for years w/a solid flat tappet cam before steppin up to a solid roller myself BUT, was told by Comp. those would be marginal at my 580+ open pressures I now run.......

Hey Dom, these are actually a new set, much stronger than the older set, can handle much more spring pressure, I talked to my friend who works tech there before ordering them, so hopefully all goes well.

""Comp Cams Ultra Pro Magnums,#1621-16""

I just emailed CC about two weeks ago about these rockers. Their reply was 500lbs open force is their spec.

Good to know. Can they handle 600+ open pressures cos I`m lookin for new bushed rockers w/out going to exotic stuff that I don`t need.

If I understood correctly, you swapped from 1.5 to 1.6? If so, you gained almost .050" in lift. Was guide-to-retainer clearance checked? (Unless I missed it.) But higher ratio rockers do put more stress on things because of faster opening and closing rates. More spring pressure is usually needed, but you seem to have a good bit.

It would seem to me that the open pressure is a moot point when it comes top the valve. When the valve is open, its just hanging there and the pressure is on the pushrod and valvetrain. When its CLOSED, that's the pressure the valve sees against the seat.

Hey Dom, I know they were ok for more than what I am running, were checked higher than what they are quoting to be safe.

I switched from 1.5 rockers to 1.6 to account for net lift loss after correcting the valvetrain geometry. Originally I had .525 net lift with 1.5 rockers and 90 degrees at full lift. After switching to 90 degrees at mid lift my net lift was .500. When I put the 1.6 rockers on my net lift is .540.

Coil bind for these springs occurs @ 1.16 according to the spec sheet.

Given that the valves actually rotated for what I believe is the first time, I'm starting to think there were some harmonics occurring.

Obviously it's time to dump the rockers but I'm thinking some different valve springs may be in order as well.

Without getting stones thrown at me, anyone ever have luck running the steel PRW rockers?

The 1.6 HS rockers in the 540 are probably the shiniest and prettiest rockers I have seen. Are they junk?

..

The problem could have simply been too much lash. There is a difference in the lash being at .025 or so in a 180 degree motor for a few seconds on the race track........and going down the road at that number at 3000rpms for sustained periods, at high engine temps.

I had some CAT stainless steel body rockers, and the roller tips started wearing down, they must have been really soft steel. I just replaced them with Harlan Sharpe rockers, no problems with those.

Nope..............like everything else, they have their place and mine are 8+ years old street/strip but low 210-235 seat and 480-500 open.......

So how did you correct the geometry when you changed rockers?

I seriously doubt that cam hurt anything. Your paultry spring pressures (by todays standard) shouldn't hurt anything either.

Are you lashing the valves one cylinder at a time or are you using the crankshaft degrees?

As said they are junk.
C.A.T NO, Needle bearing rockers NO.

Yep Crane Gold or even better Hughes.