Club Cobra - Rocker Arm Prefrence

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Rocker Arm Prefrence

Just was looking for some of what the 429/460 owners had chosen for rocker arms. I had a recent bad experience with a Crane energizer with the pin retaining the roller coming out and doing some moderate damage in the process. The heads I am using were not machined for screw in studs and use Cranes kit to allow for the use of 7/16 studs and adjustable rocker arms. Any thoughts?

What kind of cam specs are you looking at? What kind of spring pressures are you looking at?

I can't really make a rocker arm recommendation without it. Personally, I went with comp stainless roller tip pedistal mount and a jomar girdle. I'm running a roller cam with about 550 open and 150 closed and about .680 lift. My application is street/strip and I intend to rev it 7500rpm. My engine is a purpose built supercharged 429 CJ.

Depending on what you're after, this might be extreme overkill.

I like stainless rockers. They don't wear. They don't flex. They don't break. The jomar aluminum stud girdle further improves valvetrain rigidity, dampens harmonics, vibration, and audible valvetrain noise. My valvetrain is a solid roller...and you couldn't tell by listening to it.

I like the stainless rockers too. Bigger bearings on them. Have to hold up better that way. Right?

The rocker manufacturers expect people to run crazy spring pressures and crazy ramp rates on the cam profiles with stainless performance rockers...they are meant to withstand significant abuse. You'll find the bearings are bigger/better and tighter tolerance than in most cases.

If you use these in a relatively mild combo, it won't be the weak link. Be careful of some of the cheap brands...they are look-alikes and have inferior bearings and bad finish work.

If you do intend to use a girdle, make sure you use ARP studs and make sure you TELL ARP you are using a girdle...or source the girdle and the studs from the same supplier. The studs otherwise will not necessarily be perfectly concentric relative to the threads where they engage the block; and if they are not...the girdle will not fit.

Byron

Comp Cams Pro Magnum in chromoly or stainless.

Well John........looks like stainless is the way to go.

A couple of weeks ago I opened mine up because it appeared oil was getting past the intake gaskets. D3VE heads that have been machined, studs, guide plates, positive valve stem seals, dual springs with dampers. I don't know what open and closed pressures are, as they came with car, along with a bunch of issues I've been addressing one by one.

Every one of my Comp Cams Magnum roller tip rocker arms is showing signs of heat to varying degrees. Some are a little bit discoloured, while others have a very noticeable bluing where they pivot on the balls. None of the balls showed discolouration or signs of heat - just the rocker arms themselves. I suspect the pressure of dual springs is a bit much for this type of rocker arm, and just another example of the problems I've been dealing with and the improper decisions that created them.

With the exception of 4 they were a b***h to get off, as the ball fulcrums seemed to bind on the stud. Well respected local speed shop guy says apparently these balls collapse over time. Not good. One of the balls is also missing a chunk of metal. Aaaarrrggghh.

Going full roller rocker arms.