Help with pushrod measurements

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Mar 23, 2014 | 07:55 PM

02fbody35th

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From: scranton

Help with pushrod measurements

Hey guys I'm in the middle of installing a set of AI 243 heads they were milled .030. I'm also installing LS7 lifters and the car already has a gm hot cam. I just need a confirmation in my pushrod measurements. With the comp cams tool I measure out 8.5 turns 8.5x.050=.425+6.8=7.225 if I add in .075 for preload I get a 7.300 pushrod. Smallest off the shelf I found was 7.325 which would give me .100 preload. Is this to much? Now to check my measurements I used the counting of turns to reach 22ftlbs. With my tool set at 7.325 length, from zero lash to 22ftlbs I came up with 1 3/4 turns which is what's recommended. So is 7.325 where I want to be?

Mar 23, 2014 | 08:43 PM

Darkman

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From: Spring, Texas

Your calculations look correct. I don't run those lifters so I cannot speak to that preload level other than to say others on this board run that much.

Mar 24, 2014 | 04:58 AM

vettenuts

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From: Little Rhody

Trand pushrods will have them in stock and make the pushrods for most other companies including Comp.

Mar 24, 2014 | 05:31 AM

redtan

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From: Belmont, MA

http://www.briantooleyracing.com/pushrods/

BTR has pushrods less than 7.300

Mar 24, 2014 | 06:01 AM

mcdonald77

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From: Sedro Woolley, WA

I have comp 7.3's with less then 20,000 miles $60 shipped... Let me know

Mar 24, 2014 | 07:12 AM

02fbody35th

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From: scranton

Thanks for the replies guys I guess I should have looked a little better first. So should I get 7.300 or 7.325?

Mar 31, 2014 | 04:09 PM

codyseals

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Seen this and really want to know how you got that formula? New to this and really eager to learn all these formulas so I don't rely on keyboard ninjas in forums.