Who runs 7.425" pushrods?
TECH Senior Member
Joined: Jun 2016
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From: Central Cal.
Gary, that old 1/4 turn you mention, I remember well. I wonder why the LS engines dont do that? The lifters are one of the few things that are interchangeable between ghe old and new. So why wouldnt the 1/4 turn work on the LS. Actually, the first LS I ever built used SBC roller lifters, Eaton anti-pump ups. Remember them? Anyway, never had a problem with them going to 7k rpm
Joined: Apr 2006
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From: Grand Rapids, Michigan
It won't work because unlike the old smallblock, which basically had the rocker arm floating above the pushrod/ valve spring and was adjusted up and down the stud with a locknut, the LS has a smaller diameter bolt that is fully seated at all times. A non-adjustable valvetrain, basically.
TECH Senior Member
Joined: Jun 2016
Posts: 22,298
Likes: 3,619
From: Central Cal.
Gary, that old 1/4 turn you mention, I remember well. I wonder why the LS engines dont do that? The lifters are one of the few things that are interchangeable between ghe old and new. So why wouldnt the 1/4 turn work on the LS. Actually, the first LS I ever built used SBC roller lifters, Eaton anti-pump ups. Remember them? Anyway, never had a problem with them going to 7k rpm
My fault. I know they aren't adjustable. I should've worded it like; why not obtain just .010"-.020" preload from zero lash? I don't remember the thread pitch of the SBC rocker stud, been involved in these LS builds for so long. So let's assume the SBC used either 3/8-16 studs, or 3/8-24 studs. The 1/4 turn on the 16 pitch would be approx .016" from zero, not counting the rocker ratio. The 24 pitch would be approx .010". My memory is going 3/8-24, so about .010" preload. Whatta ya think?
Launching!
Joined: Oct 2022
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From: FL
That's about .100 short of what I like to run. I run my ls engines in the .100 to .120 preload range.
But to your point maybe. Remember the net lash GEN 5 big blocks? There was a stud kit available to make them adjustable like the old style. IIRC they were 8mm too. Wouldn't be too hard to set that up on an ls. Except for maybe keeping the rockers on the valve tips.
But to your point maybe. Remember the net lash GEN 5 big blocks? There was a stud kit available to make them adjustable like the old style. IIRC they were 8mm too. Wouldn't be too hard to set that up on an ls. Except for maybe keeping the rockers on the valve tips.
