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Old 07-04-2008, 11:02 AM   #90
Jeff Lee
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Join Date: Jul 2007
Location: Anthem, Arizona
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Default Re: Roller Rockers in Stock

I can't imagine that a 6500 RPM stocker is considered "high" RPM. But high or not, it was with larger or more radical camshaft design that the car responded with quicker ET's and faster MPH's, with the limitation on upper RPM being placed on the small Autolite carb I ran. Now I guess if I were on the outside of the conversation listening in, I would maybe say "so Jeff Lee, I'l bet you never got that AMC 390 to run very well because obviously you don't have a handle on the valve train issues". Well, the best times were 10.500 @ 125.01 in D/S in what was "killer" air; in Arizona (which never see's air like the sea coast tracks). But typical would be a 10.62 @ 124.7 @ NHRA events.
So I guess that would lead me to "so your saying I need to lower the RPM and ET/MPH to save the parts"? Well tried that. All I can say is it went slower. And I guess for me that's a bitter pill to swallow.
Now I also have spoken to Vic Guillimo (I know, incorrect spelling). His 429 Ford, which is equally as fast but in D/SA, tells me he breaks rockers more frequently than even I did. Clark Holyrod came up with a substantially larger system which he markets to reduce or eliminate breakage. Aparently he, and his (many) customers along with Vic & I haven't been able to come up with the camshaft that will work in Stock that gives a 3-1 safety margin on rocker safety. Maybe the answer is a "pure Stock" cam?
Now if I had to guess at the one thing these racers mentioned above have in common is high compression ratio's on their NHRA blue-printed engines (429/396-375/427-425, etc.). Maybe that's part of the issue as well, I don't know. I just know they have issues, not just stupid old Jeff Lee.
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Last edited by Jeff Lee; 07-04-2008 at 05:07 PM.
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