shaft roller rockers

I wanted to post this question here since i didn't get a good response on it in the past on the other forums and since all the knowledgeble crowd is here ...

I have DART pro 1 aluminum 215's on my engine. The valve are somewhat spaced apart (believe 60/40), because of this my crane gold race rockers sit angled toward the valve and clearance of the pushrod to the head is minimal.
The manufacturers suggest shaft rollers because this could lead to a problem later on.

Is this true. Some say this is not a problem.

Yes, you can get shaft rockers with offset rocker bodies, this way the pushrod is always perfectly aligned and the shaft nose is centered over the valve. It's almost a must when using wider spaced valves.

It's not uncommon however for a rocker to not sit centered over the valve, even ordinary heads like edelbrock rpms and such suffer from this, usually on some not all valves. If you have the clearance and the valve stem is not contacting the rocker completely on the side of the nose (roller) then it would be fine if there are no clearance issues elsewhere. The shaft rockers however would be the ideal, yet costly, solution. You would also have ot figure out what offset rocker to use where exactly. Just a set of shaft rockers is not the fix if you don't use offset bodies.

The ". . . later on." part of your post probably refers to the side-loading of the valve that will accelerate valve guide wear which'll show up over time. Biggest problem with that is once the wear causes excessive clearance the valve(s) won't seat properly, oil migrating between the valve stem and guide will increase and the only way to fix the problem is to pull the heads for new guides to be installed.

I once built a 434 L98 using 15* Brodix heads and it took some serious off-set rockers on a Jesel shaft system to properly position the rocker tips.
That engine also called for some custom made pushrods. Talk about a valvetrain nightmare!!

I'd err on the "ounce of prevention . . ." adage.

Jake

So basically it would be better to migrate to shaft rockers. Jesel has a system that is specifically made for the offset needed on these heads.

Thanks all,

Yves

yup :idea:

Jesel's the high-end setup, meaning high $$$$$$. I believe there are less expensive setups that'll work just as good, especially on a street engine.

Jake

In my new engine with Dart PRO1 227cc CNC I use Crane Shaft Rockers !

There is a version designed for Dart Heads.... very nice product, with bearnings instead torringtons !