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Discussion Starter · #1 ·
So i have a soild flat tappet comp cam . 460 1.73 roller rockers ,all new .
With push rods that are 5/16 ,8.650.
There too short.
In order to.get the roller in the center of the valve stem , using a pushrod tool ,i need 9 inches . I must be missing something ???
 

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Type of rocker?
Type of cylinder head? SCJ / P51 / AFR ???

Deck height?


More information about your build is necessary !!!







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Discussion Starter · #3 ·
C9 heads never been cut to my knowledge.
The short block hasn't been build , so stock to my knowledge. Thinest head gasket i could find . Performance world (cheap) rockers .
 

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So i have a soild flat tappet comp cam . 460 1.73 roller rockers ,all new .
With push rods that are 5/16 ,8.650.
There too short.
In order to.get the roller in the center of the valve stem , using a pushrod tool ,i need 9 inches . I must be missing something ???
Quit trying to center the roller wheel over the center of the valve stem--roller placement atop the tip of the valve has literally nothing to do with valve train geometry, and that is the "something" that you are missing.

Your pushrod length is excessively long specifically because you are fixated on centering the roller wheel atop the stem. Because of that, you are lengthening, and lengthening, and lengthening the pushrod in an attempt to radially "swing" the rocker around until the roller wheel is planted exactly where you want to see it. In other words, you are positioning the roller wheel at the expense of optimized valve train geometry.

The internet is wrong--valve train geometry is not solely about inspecting a roller wheel's wear pattern on the tip of the valve. Rocker arms are radial devices that transmit linear information from the cam lobe (via the pushrod) to the valve, and so this articulating device we call a rocker arm needs to be geometrically optimized around the other moving parts with which it functions. Where the roller wheel rests atop the valve has nothing to do with that.
 

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Paul K. is correct. Adjust pushrod to set rocker arm trunion centerline 90 degrees at 1/2 lift, jim miller rockers style.
 

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Yes well worth buying from Jim Miller his mid-lift calculation. an absolute must imo

once you have sorted the geometry then a pair of adjustable pushrods for your length patterns. then make or order.
 
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