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LS7 lifters milled .30 862 for 5.3L, what pushrod length???

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Old 01-18-2013, 08:46 AM
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Default LS7 lifters milled .30 862 for 5.3L, what pushrod length???

I currently have 7.4s

I am ordering a pushrod length checker with my new pushrods

The truck is a daily driver so it can't sit in the shop waiting on pushrods to come in the mail.

What length worked for you with this set up??? I was thinking 7.35 Would work till I know for sure with the length checker to order the exact ones.
Old 01-18-2013, 09:10 AM
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7.375 should work
Old 01-18-2013, 09:17 AM
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There is no clear cut answer in a situation like this. Length needs to be checked first. Order the checker, measure, then order pushrods. Just my suggestion.
Old 01-18-2013, 11:28 AM
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I have a similar setup; 5.3L LM7, Ls7 lifters, 799 heads milled 0.022, LS9 head gasket (stock thickness) and I'm running 7.325" pushrods to get me around 0.075" preload, measured with an adjustable pushrod and dial indicator. But as mentioned, you must measure to know for sure.
Old 01-18-2013, 12:26 PM
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Also a similar setup. LM7, 243's milled .030, LS7 lifters, .040 thickness gasket ---- 7.350 pushrods.
Old 01-18-2013, 01:19 PM
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OP, see what I'm saying....3 different lengths with similar setups. Best to measure first, and not regret it later.
Old 01-18-2013, 01:20 PM
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Originally Posted by dmelvin
Also a similar setup. LM7, 243's milled .030, LS7 lifters, .040 thickness gasket ---- 7.350 pushrods.
Whats your preload? It's a little worrying that no one else is using pushrods as short as mine
Old 01-18-2013, 02:52 PM
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Originally Posted by Ferocity02
Whats your preload? It's a little worrying that no one else is using pushrods as short as mine

Actually I'm using the same length as you but I did check mine nore than once

But like everyone said its best to be safe than sorry...
Old 01-18-2013, 05:10 PM
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Originally Posted by way2much_01
Actually I'm using the same length as you but I did check mine nore than once

But like everyone said its best to be safe than sorry...
Ah good. Not too many people using pushrods this short. I measured every valve with a dial indicator and the average was around 0.075". Not sure exactly what the high and low were, but the spread was probably 0.015-0.020".
Old 01-18-2013, 06:38 PM
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Definitely order the checker, I assumed mine was 7.4. After installing they were too tight, and after getting the checker I realized I was .05 off. Checker was around $25 and is cheap insurance!
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