roller rockers

[Alan Roehrich]

Comp Cams has a new Ultra Pro Magnum Series chrome moly steel rocker that uses a 1/2"-20 stud, for the big block and small block Chevy. It is the result of some serious efforts by Tim Cole and myself since the roller rocker rule was announced. The new rocker accepts an ARP Pro Series rocker stud that is 1/2"-20 on top as opposed to 7/16"-20, made exclusively for Comp Cams by ARP. The rockers are rebuildable, and the body is guaranteed for life against breakage.

[Bill Edgeworth]

Originally Posted by R. Thorne

Thanks, Bill, any particulars (how much more lift and how much shorter pushrods?). Also, were the Harland Sharp rockers the standard ones, diamond series, or HD ones? PM me if you prefer. Thanks, Ron.

My numbers in relation to your situation are totally irrelevant unless everything was exactly the same including seat pressure/spring combo, same stamped steel rockers, head geometry, deck height etc. I’m not sure that Pontiac made these heads all that accurate; I have a couple different sets of 6x heads that are supposedly prepped identically but require different pushrod lengths. That leads me to believe the rocker stud placement is not all that accurate. So what I can tell you is that in my case they produced 0.007 more lift and took almost 1/10” reduction in pushrod length. The Rockers are just the S6001 that’s all you need with your combo, its low lift and low RPM.

[R. Thorne]

Thanks for your input, Bill. I understand that apples should only be compared to other apples and not pears, but your real world experience was exactly what I was looking for pertaining to ratio and flex. Thanks again, Ron.