RockinWs6

Why do people waste so much time on this..........its no different than 40 years ago.

SPRAYED 01

iTrader: (22)

Its a simple discussion on a tech message board, not a big deal.

crainholio

iTrader: (2)

I don't understand why you keep referring to the the rocker bolt as a nut.

Please explain to me what you don't understand about the difference between a bolt and a nut?

RockinWs6

You know exactly what I meant..........

railmule

wtf does it even matter? nut,, bolt same damn thing...

crainholio

iTrader: (2)

Pure mechanical genius on display, from the guy who tried to fix oil burning with a tune:

https://ls1tech.com/forums/generatio...e-exhaust.html

showvette

When counting turns past zero lash, remember you're only supposed to torque the bolt to 22 foot pounds.

Frank

showvette

This is the method I followed...

M6 Swap

iTrader: (1)

awesome info showvette, thanks

showvette

I hope it helps. It took alot of confusion out of things for me.

01ssreda4

iTrader: (96)

That was Shane at Thunder Racing's way to do it. And yes it works.

And to the damn fool who is saying .10 is acceptable pushrod preload, shoot yourself because that's ridiculous.

soundengineer

iTrader: (16)

this measurement is incorrect, and your desired preload is incorrect with an aftermarket cam


first off...aftermarket cams want to see .020~.060 preload...and yes, it does make a difference, the extra ramp rate will want less preload to make it quieter, and it will make slightly more power with less preload, and have more valve control.

secondly...the math for preload needs to account for rocker ratio as well
so ...Thread pitch of 1.25 = .0492126
but that assumes 1:1 rocker....
with a 1.7:1 rocker (stock LS1), it becomes 0.0492126 + (0.0492126/1.7) = .078161 per one turn of rocker bolts......

if you dont believe me, Use a Dial indicator, and you will see one turn is .078

showvette

I'm at .076" preload with my COMP XER 281 with 7.4" pushrods. COMP told me that was on the high side, but it shouldn't affect performance. Their "ideal" spec for my cam is .060" preload. I asked if I should change to a shorter pushrod and they told me not to worry about it.

Frank

SPRAYED 01

iTrader: (22)

This is why I ask questions and make. Threads. You can have so many people thinking one thing, then some one comes a long with new info and makes everything else incorrect.

Little to late, all ready installed 7.430 pr because with the 7.4 i was getting about one full turn. So I guess im at like .100 preload, awesome.

showvette

I'm at 1 5/8 turn, using the method listed above. 1.63 turns X .047" = .0766"

Frank

SPRAYED 01

iTrader: (22)

If sound engineer is correct you're at like .128

showvette

The method I posted above is widely used and it's accurate. A pool among all instructions tell you that 1 1/4 and 1 3/4 until you get to 22 foot pounds seems to be the common consensus.

Frank

SPRAYED 01

iTrader: (22)

Frank, I hope your right because that's the method I used. I wish I had just simply checked with a dial indicator but I didn't.

Scoggin Dickey

iTrader: (34)

There is a ton of misinformation in this thread, and it's on both ends of the spectrum. If you aren't going to buy a $20 checker, please just follow Shane's instructions that were posted above. No less than 1 turn of the bolt should be considered acceptable with gm lifters. If possible I like 1 1/4 to 1 1/2, it will be quiet and stable. A little more is acceptable and is generally not a problem.

SPRAYED 01

iTrader: (22)

the pr checker isnt the question now,its how much preload is in one full turn with 1.7 ratio rockers? Any one have their valve covers off and a dial indicator?