nvr enough

iTrader: (2)

I'm running morel lifters with stock rockers and 7.4" pushrods..I get 1-1/2 turns to torque (22lb) when checking preload. Do I have the correct length pushrods?

The more I read about checking preload, the more confused I get.

Thanks in advance.

Sales2@Texas-speed

iTrader: (5)

Which morel lifters are you running so that we can see what the recommended preload is for them? You're at about .076" or so of preload currently, assuming that was 1.5 turns from zero lash.

vettenuts

iTrader: (4)

You may have too much. The Morels I am running require 0.030"-0.050" preload.

nvr enough

iTrader: (2)

After finding, and googling the part number, I found I'm running the "street" morels (5290's).

Although I can't figure out the math aspect, from what you guys are saying, my pushrods are a little to long, right?

I appreciate your responses.

nvr enough

iTrader: (2)

I've been trying to figure out the math, but I still don't get it. I don't see how you guys are doing the math?

Should I sell my 7.4's, and get some 7.375" pushrods?

Darkman

iTrader: (2)

The math is discussed in this thread:

https://ls1tech.com/forums/generatio...re-load-2.html

Monte4ever

iTrader: (2)

It looks like you are adding the total amount of turns that it takes for you to reach your torque value to your preload count which is not the correct way. Preload on a LS based motor is when the rocker arm makes light contact with the pushrod while its resting on the lifter seat. Then watch how many turns it takes for the rocker arm bolt to stop turning BEFORE you apply torque to the bolt. If I'm wrong in my assumption then sorry lol.

nvr enough

iTrader: (2)

Thanks.

So if I'm at .076 preload now roughly, and .050 seems to be my target, a 7.375 pushrod should put me at about .051...correct?

nvr enough

iTrader: (2)

I'm going by what this says...but the way I read it, makes me think it's the total amount of turns it takes to reach 22ft. lbs., after reaching 0 lash



1. Using the EO/IC method, get the lifter to the base circle of the cam.
2. Using a known length pushrod (7.400" is a good start with stock rockers) run the rocker arm bolt down to zero lash. This is easily done with your fingers "wiggling" the rocker, the point at which the "slack" is just gone is zero lash.
3. Set your torque wrench to 22 lb./ft. Tighten the rocker to full torque and count the number of turns it takes to get there. 1 full turn wtih a stock 8mm X 1.25 bolt is ~.047" preload as measured at the pushrod/rocker interface.
4. I normally shoot for 1 1/4 to 1 3/4 turns with stock type lifters like Comp 850's, LS1, LS7 etc.

For an example, if you use a 7.400" pushrod and come up with 3/4 of a turn, you will need at least .025" longer pushrod to get into range. If you end up with 2 1/4 turns, you will need one .025" shorter...

vettenuts

iTrader: (4)

The counting turns method isn't real accurate, but based on Shane's posts and my verification with a dial indicator, you need one turn from zero lash to 22 lb-ft. Morel's don't like too much preload and will hold the valves open if they have too much, so it would be best to measure and make sure of your preload.

Darkman

iTrader: (2)

Using your measurements and the corrected math for the number of turns (see the other thread), your current preload is about 0.091 with the 7.400 pushrod. Since Morels use a preload of 0.030 to 0.050, you presumably need a pushrod of 7.339 to 7.359. A 7.375 pushrod would put the preload at 0.066 which is too much. A 7.350 pushrod would put the preload at 0.041 which is in the middle of the range for Morels.

nvr enough

iTrader: (2)

okay. thank you all for your help.

nvr enough

iTrader: (2)

I picked up a set of 7.350 pushrods, and double checked my preload on a couple different cylinders (I only checked one the first time). I get 1-1/4 turns on some of the bolts, which if I'm understanding this correctly, puts me over .050 preload...and in doing some reading, I'm running an iron block/aluminum head combo which should even have a little less preload.

You guys think I should I take these 7.350's back and get some 7.325's? Or just run these 7.350's?