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Old 04-22-2011, 01:34 PM   #7
Jeff Lee
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Default Re: Holroyd BBC Rocker Arms

Quote:
Originally Posted by Grant Eldridge View Post
Someone asked, so here's a photo of Clark's rocker. The cross inside identifies the marine 502 rocker, the insert is shown separately to one side....Sorry, I don't have a photo of the special high strength stud and adjuster that are used with the rocker arms. I went to these after noticing that the stock sized ARP studs used with the Crane rockers I had been using were bending as I turned the motor over due to the high spring pressures we were using......
Grant Eldridge

I take it that insert fits under the welds on the push rod side of the rocker arm?
That's a bunch of bull crap that this is legal. Not only is the part heavily modified, it doesn't even look stock when it's all done. I believe the rule book is clear on this issue. Either the rule book needs to be amended to reflect allowable modifications or the rule needs to be enforced.
I've long known about this 502 rocker swap but was not aware the rockers were welded and support bridges attached. Had this type of modification been specifically accepted in the rule book, I would have kept my car in D/S for it was the constant rocker issues that wore me out while at the races. The allowance of a T&D shaft rocker in SS is what pushed me over from Stock to SS. Sure makes it a lot easier to maintain valve train integrity.

Somebody should pull up the thread I started on Stock Eliminator roller rockers (it's been so long, maybe 5 years that I doubt it's even archived here). But the gist of it was that with all the other items allowed (Schubecks, tool steel lifters, billet cam cores, fat pushrods, 9/16" 502 marine, tool steel and premium after market cast rockers, etc.) it no longer made sense to run a stamped steel OEM rocker. Boy, was I chastised as yet another placing nails in the coffin of Stock! I also heard how I didn't know how to correctly fix the problem with proper geometry or cam profiles. Obviously, my pain of yesteryear is felt by many as there is a burgeoning industry that is allowed by NHRA despite how the rulebook is written.
As I was told, if you can't make your engine live under the guides of the rulebook, get out! I did, and the financial outlay has been huge. Seeing these "allowable" rockers makes me second guess my decision to get out of Stock as I know with what I know now, 10 thirties is not out of the question in D/S for me.
My long standing opinion is OEM configured or mounted roller rockers should be allowed in NHRA as is IHRA. That means Crane or similar brand stud or shaft mounted (replicate OEM mounting) aluminum roller rockers that generally speaking sell for about $279.00. I fail to understand the logic that this should not be permissible.
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Last edited by Jeff Lee; 04-22-2011 at 01:36 PM.
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