In hydraulic cam application I've seen many roller rocker fail at the roller tip. This seems to be because there is no valve lash to make things "turn" and let the oil in. Hydraulic lifters actually preload things a little.

In general at the rocker pivot I've seen hydraulic cams wear valve train more than well maintained solids.

I'm trying to figure when one should use rockers with roller tips or roller pivots.

I figure solid cams - rollers at each point.
Hydraulics may be influenced on the method of oiling the pivot and tip.

Also FE's only splash feed the ball and cups of the push rods so lube is better here for solids too.

So how good are Roller Rockers. is there weight inertia as good as the factory style adjustables. Are rollers rocker good marketing or good engineering.


just thinking at the keyboard

 

I've never had a failure running roller rockers with a hydralic cam. A lot of the crate engines and some production blocks come with these as standard equipment.

Now most of this comes from running small block engines with a roller pivot. On a FE, the only roller pivots available come from Rocker Arm Specialist and Erson. Is the wear you are talking about at the pivot on a non roller FE aplication?

The roller setup from Rocker arm specialist uses the same style of pushrods as the stock solid setup so the wear there should be the same.

Are the roller rockers good? Yes! They reduce friction, reduce valve guide wear, and some say they reduce oil temp. The weight inertia is as good as the factory style or better. Remember that these were designed for racing applications. Are they worth the cost on a motor that is driven on the street? Probably not, but they sure look good before you bolt on the valve cover!

Reggie

 

>I've never had a failure running roller rockers with a
>hydralic cam. A lot of the crate engines and some production
>blocks come with these as standard equipment.

Some Holden engine recently had Crane roller rockers.
I've seen 2 full set wear flats on the roller tips.
The same on a solid cam wear fine.

>Now most of this comes from running small block engines with
>a roller pivot. On a FE, the only roller pivots available
>come from Rocker Arm Specialist and Erson. Is the wear you
>are talking about at the pivot on a non roller FE
>aplication?

On an FE i've noted that for std rockers, solid cams wear the pivots less.

>>The roller setup from Rocker arm specialist uses the same
>style of pushrods as the stock solid setup so the wear there
>should be the same.
>
>Are the roller rockers good? Yes! They reduce friction,
>reduce valve guide wear, and some say they reduce oil temp.
>The weight inertia is as good as the factory style or
>better. Remember that these were designed for racing
>applications.

or to supply a market (synical huh ?)

Are they worth the cost on a motor that is
>driven on the street? Probably not, but they sure look good
>before you bolt on the valve cover!

hmm expensive hidden decoration
>
>Reggie

 

Being cynical is a good thing! As for the expensive, hidden, decoration, I got a little carried away. I was looking for a stronger rocker arm support and had to replace or rebuild the rocker arm assemblies anyways. Maybe I can put a glass window in the valve cover.

I don’t think that the preload on the hydraulic lifters would cause the premature failure. On roller hydraulic setups, the roller always has preload but I have not heard of any failures. Maybe a lack of oil on the roller tips? Or maybe just bad luck on the manufacturers end?

If I have any failure on my setup, I'll post it. But right now I'm not putting too many miles on the truck. Had a real bad accident caused by an unlicensed, uninsured, probation violating, illegal alien MF! Won't be driving for a while....

Reggie

 

The rockers have a special situation.
The lifter "ensure" minimal lub between roller and valve stem and rocker and shaft. The also dont get the chance to roll but oscillate about a small arc of movement.

 

Something I was reading at Harland Sharps web site is that with the roller rockers you should set the valve train at no more than 1/2 turn after zero lash with the roller rockers. I don't know if tightening it more would cause that problem or not, But it is something to think about.

 

I got a reply back from Jeff at Harland Sharp and this is what the reply was.

"The tips will wear flat if you put to much pre-load on the lifters. Should only have to preload the lifter 1/4 to 1/2 turn."