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At what point are different length pushrods necessary?

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Old Jan 7, 2005 | 04:10 PM
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Default At what point are different length pushrods necessary?

At what point are different length pushrods necessary? I am using a .045 gasket (~.010 shorter than stock), and am curious at what point shorter pushrods become necessary? With heads milled .020? .030? .040? .050? The cam is ~.030 smaller than factory cam, so doesn't that make up for the first .030 (head milling and gasket difference together)?

Thanks, Shawn
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Old Jan 7, 2005 | 04:16 PM
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When the contact area on the valve tip is wider then .060" and not centered in the valve with contact area favoring the intake side of stem. Use a felt tip marker to check this.

Chris
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Old Jan 7, 2005 | 06:42 PM
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http://www.holley.com/HiOctn/TechSer...ECVTTech1.html
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Old Jan 7, 2005 | 06:47 PM
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Great link Viper. I'm gonna test mine some day.
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Old Jan 7, 2005 | 07:37 PM
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In short when geometry is altered from optimal and when you cannot atain the proper lifter proload. The reason there is seldom problems with ls1 combos is that the stock lifters have quite a wide variation in acceptable preload. However, geometry may alter to the point of different pushrods may be necessary. Theoretically you should start the rocker tip at the intake side of the valve stem at zero lift, the rocker tip should be in the middle during mid lift, and the rocker tip should be just to the exhaust side of the valve stem during peak lift.
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Old Jan 7, 2005 | 10:43 PM
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Hey...

I know where you got that...



Ed
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Old Jan 7, 2005 | 10:52 PM
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good info
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Old Jan 7, 2005 | 11:06 PM
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Originally Posted by pdd
good info
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Old Jan 8, 2005 | 07:35 AM
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Ed,

From you of course! Got the notice, the pushrods, lifters and timing chain are en route.

Let me know about milling as it pertains to this thread.

Thanks!

John
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