Lifter Preload Help!!!!

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Dec 28, 2005 | 07:50 PM

#21

vettenuts

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From: Little Rhody

Is that 0.075 at the rocker thread? If so, with stock rockers, you need to multiply by 2.54/1.54 to get the actual preload at the lifter.

Dec 28, 2005 | 07:53 PM

#22

Haans249

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From: Fort Worth, TX

The best way to get the proper preload on these lifters, is to install the lifter as normal, then drop in an adjustable pushrod length checker, then, install your rocker and trq down to 22ftlbs. Then adjust the pushrod till you have zero lash at the rocker base, remove, then measure. Then add .030 to that measurement. That got me to .035 preload, so its a good method.

Adrian

EDIT: forgot to mention that you have to make sure you're on the base circle of the cam lobe you're measuring on...

Last edited by Haans249; Dec 28, 2005 at 09:50 PM. Reason: forgot something

Dec 28, 2005 | 08:37 PM

#23

white2001s10

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From: Fairview Heights Illinois

Quote:

Originally Posted by John02SS

Had a set made from Crane and they were total GARBAGE. Varied .030 from shortest to longest and was told that is as good as it gets. It is been a hassle!

holy hell!

They made you an extra special set of variable length pushrods. I bet you feel really special.

Dec 28, 2005 | 09:59 PM

#24

John02SS

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From: Pace, FL

Quote:

Originally Posted by white2001s10

holy hell!

They made you an extra special set of variable length pushrods. I bet you feel really special.

I was a lil surprised by it to say the least!

I expected more I guess! They were truely custom though!

Dec 29, 2005 | 05:16 AM

#25

Viper

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From: Cleveland, OH

Quote:

Originally Posted by vettenuts

Is that 0.075 at the rocker thread? If so, with stock rockers, you need to multiply by 2.54/1.54 to get the actual preload at the lifter.

WHAT??? I have never seen that yet....

Dec 29, 2005 | 07:49 AM

#26

vettenuts

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From: Little Rhody

Quote:

Originally Posted by Viper

WHAT??? I have never seen that yet....

Here is my figuring. The rocker tip is on the valve spring. The valve spring won't compress (assuming you are on the base circle of the cam all of the preload will be at the lifter). As you tighten the rocker, it will pivot on the valve spring through the lever ratio because you have two similar triangles, so the ratio is the distance from the valve tip to the pivot point and the distance from the valve tip to the pushrod. The stock rocker is about 1.54 rocker ratio at rest, so the ratio is 2.54/1.54 or approximately 1.65 times the rocker movement.

Hope this explains it, but it makes sense that if you tighten the rocker down the pushrod will move more than the rocker pivot point.

Dec 29, 2005 | 08:52 AM

#27

CAT3

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From: Sierra Vista, AZ

Quote:

Originally Posted by Viper

CAT3,

What preload do you have on the Morels now? I have .075 ( if a 1/4 turn on a stock rocker = .015, then 1.25 turns = .075, search is down ) but need to bring it down to .030.

I can check again when I get home next week, but honestly not sure right now.

Whats the operating range of the Morels?