Which Roller Rockers?

[ERA Chas]

Originally Posted by cobrarkc

What do they run I can get the needlebearing HS's for $950

I'll say again-you DON'T want needles. Bushed is stout enough with good oiling. I raced the crap out of them for a long time.

[patrickt]

Originally Posted by ERA Chas

I'll say again-you DON'T want needles. Bushed is stout enough with good oiling. I raced the crap out of them for a long time.

But if you care to make an informed decision, and to understand the issue, read on...

Why Ersons Have Needle Bearings
April 7 2003 at 1:10 PM RobbMc (Login RobbMc)
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I have been asked why Erson rockers use needle bearings, why the shafts and stands are included and why they cost so much.

Yes, I will admit that with pressurized oil and moderate loads, aluminum on steel will work, kind of. I still say it's a compromise. Here are the real reasons some companies run aluminum rockers directly on steel shafts: (I know this because these things were considered when I designed the Erson rockers):

1. Bearings cost money.
2. If needle bearings are used, the shaft must be case hardened at least .030" deep. This is difficult and expensive because the shafts are so long and tend to warp during heat treat. Plus it's expensive and you have to grind them twice and straighten them between grinding.
3. It's difficult to find needle bearings that will fit the stock diameter shaft so that means custom shafts need to be made.
4. Even if you can find needle bearings that will fit the stock diameter shaft, you still need to heat treat them for needle bearings.
5. If you use stock diameter shafts and machine the rocker bodies for bearings or bushings, the bodies get too thin around the bearings. So you are back to making custom shafts.
6. If you make custom shafts, then you also need custom stands to hold the shafts, and that costs more money.
7. Unlike stud mounted rockers, FE rockers oil through the shafts and thus have pressurized oil to the pivot point rather than splash fed oiling. In theory, almost any material can be used as a bearing material as long as you have a constant supply of pressurized oil.

So, as you can see, there are many reasons that most companies simply bore the I.D. of the rockers to fit the stock shafts. Most of them involve saving money and being able to sell rockers at a lower price. Their rockers will work, more or less, if the oil supply is constant and the loads kept low. However, I talk to customers almost daily (FE and Mopar) who have switched to rockers with bushings or bearings because solid roller springs have caused their old rockers to either wear too fast (constant lash changes) or seize on the shafts and break.

Have you ever messed around with Olds V8's? They used these silly little aluminum pivots in the stock pedestal style rockers. Even with stock springs, the pivots wore out after about 75 or 100,000 miles. And since the rockers aren't adjustable, they start making all kinds of ticking noises. If you run stiff valve springs, the aluminum pivots where out so fast that you have to carry spares in your glove box. I've even seen them gall so bad that it looks like aluminum has been welded to the steel rocker body.

Anyway, that's why Erson rockers ended up with needle bearings, custom shafts and custom stands with end supports. And THAT is why they cost $625. Still, if rockers without bearings or bushings will work for you, stay with them and save some money so you can buy other things. Besides, those damned Erson rockers are always on back order.