Just what he said 
"Poly lock" specifics and recommendations
Thread Starter
Team Owner
Joined: Jun 2004
Posts: 20,216
Likes: 4
From: Smile, it's just the internet.
"Poly lock" specifics and recommendations
Hey all. I'm fed up with my factory-style rocker adjusting nuts. I've replaced all the nuts and studs and STILL can't get them to hold adjustment. The nut tension is all over the place and I'm using Federal-Mogul/Dana hardware! These are holding down factory-style stamped rockers/*****, solid lifters, and don't see any severe lift, but DO see 6500 rpm regularly.
I want to move "up" to a poly lock type nut in the hopes of reducing maintenance and increasing accuracy.
Do they really work?
Is one better than another?
Do they fit under short valve covers?
Any special tools needed to ease installation/adjustment?
Anything else I should know?
Thanks!
I want to move "up" to a poly lock type nut in the hopes of reducing maintenance and increasing accuracy.
Do they really work?
Is one better than another?
Do they fit under short valve covers?
Any special tools needed to ease installation/adjustment?
Anything else I should know?
Thanks!
Pro
Joined: Nov 1999
Posts: 520
Likes: 5
From: Front Range
They work great. Just make sure it's high PSI steel, and not from China. I've had some chinese adjusting nuts chip at the bottom face, leaving debris in the valvetrain area. Not something I want cruising through my rocker bearings.
As for adjustment, most people just crank them down pretty hard with a combination of an open end wrench and an allen wrench. If you want to do it by the book, you need a special valve adjustment tool like they make for motorcycles, where you can actually attach a fishing scale to one end and calculate for proper torque. Then again I don't even know if they make these tools in sizes to work for our motors. Now you've got me curious...
i'd say go for it. It sounds like your rocker studs are a little worn. Are they pressed-in or screw-in studs?
the blonde weasel
As for adjustment, most people just crank them down pretty hard with a combination of an open end wrench and an allen wrench. If you want to do it by the book, you need a special valve adjustment tool like they make for motorcycles, where you can actually attach a fishing scale to one end and calculate for proper torque. Then again I don't even know if they make these tools in sizes to work for our motors. Now you've got me curious...
i'd say go for it. It sounds like your rocker studs are a little worn. Are they pressed-in or screw-in studs?
the blonde weasel
Race Director
Joined: Oct 2000
Posts: 14,967
Likes: 79
From: central FL, near the beach.
when u show off your nuts at a car show poly locks look/work fine.
An equally effective fix is to double nut it and torque the top nut(std. or narrow type) to 20# while holding the lower nut. Caution: girls may call you bubba when they see your nuts)
An equally effective fix is to double nut it and torque the top nut(std. or narrow type) to 20# while holding the lower nut. Caution: girls may call you bubba when they see your nuts)
Le Mans Master
Joined: Oct 2001
Posts: 5,943
Likes: 3
From: Wildwood IL
Had the same problem. Sub 500 lift cam with Comp roller tip rockers. Posi Locks STAYED PUT. Just don't crank on the set screws...I've seen an overtightened set screw actually break the rocker stud. (not ARP studs) I had tall valve covers, so I don't know if they'll work with short.
Eddie
Eddie
Racer
Joined: Feb 2005
Posts: 317
Likes: 2
From: coral gables miami
Not exactly what you want to hear, but you cannot beat new OEM parts for longevity in the valve train with few exceptions and poly locks and roller stuff are not one of them for basically street applications.
Le Mans Master
Joined: Mar 2004
Posts: 7,437
Likes: 1,463
From: Little Rock AR
I think the proper procedure to tighten the poly locks is like this:
set the valve lash with the outer nut.
Back off 1/4 turn or so
tighten the set screw against the stud
Then tighten both the nut and the set screw at the same time 1/4 turn to get back to the proper lash setting.
Check with someone who manufactures them before taking my word on it.
-Mark.
set the valve lash with the outer nut.
Back off 1/4 turn or so
tighten the set screw against the stud
Then tighten both the nut and the set screw at the same time 1/4 turn to get back to the proper lash setting.
Check with someone who manufactures them before taking my word on it.
-Mark.
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Race Director
Joined: Oct 2000
Posts: 14,967
Likes: 79
From: central FL, near the beach.
Originally Posted by Matt Gruber
when u show off your nuts at a car show poly locks look/work fine.
An equally effective fix THAT FITS UNDER A LOW VC is to double nut it and torque the top nut(std. or narrow type) to 20# while holding the lower nut. Caution: girls may call you bubba when they see your nuts)
An equally effective fix THAT FITS UNDER A LOW VC is to double nut it and torque the top nut(std. or narrow type) to 20# while holding the lower nut. Caution: girls may call you bubba when they see your nuts)
Melting Slicks
Joined: Jul 2002
Posts: 3,000
Likes: 22
From: Boulder Creek California
I have had mine about 6 months, they have all held their settings perfectly. This isn't a free pass to never check your valves again but I do trust them more than the stock nuts. I had a valve spring break the other day and I didn't hear it for a while, if the nut had moved my luck probably would've run out. I think they're CompCams brand.
I just adjust with the main nut and hold it in place with a 5/8" box wrench while tightening the setscrew. If you have solid lifters and need better precision, start a little loose before tightening the setscrew and recheck. That's something you have to get a feel for.
-Chris
I just adjust with the main nut and hold it in place with a 5/8" box wrench while tightening the setscrew. If you have solid lifters and need better precision, start a little loose before tightening the setscrew and recheck. That's something you have to get a feel for.
-Chris
Last edited by LiveandLetDrive; May 25, 2005 at 01:13 AM.
Team Owner
Joined: Jul 2004
Posts: 40,275
Likes: 786
From: Redondo Beach, California
Before I used my Poly-Locks, I removed the rocker arm studs and had the ends machined flat. The stock studs are not really that flat. Now with the machined flat studs, I could use the outer adjusting nut for the correct rocker arm clearance, and then use the allen wrench driven insert to torque into the stud and lock-up the entire mechanism. In other words, polylocks work best if the top of the rocker arm stud is exactly flat. Usually they are not exactly flat without machinging.
I initially had a great deal of problems with rocker arms working loose. After the above procedure, I never had a problem again!
I initially had a great deal of problems with rocker arms working loose. After the above procedure, I never had a problem again!
Last edited by 68/70Vette; May 25, 2005 at 10:56 PM.
Melting Slicks
Joined: Nov 2003
Posts: 2,362
Likes: 1
From: San Antonio TX
Originally Posted by 68/70Vette
Before I used my Poly-Locks, I removed the rocker arm studs and had the ends machined flat. The stock studs are not really that flat. Now with the machined flat studs, I could use the outer adjusting nut for the correct rocker arm clearance, and then use the allen wrench driven insert to torque into the stud and lock-up the entire mechanism. In other words, polylocks work best if the top of the rocker arm stud is exactly flat. Usually they are not exactly flat without machinging.
I initially had a great deal of problems with rocker arms working loose. After the above procedure, I never had a problem again!
I initially had a great deal of problems with rocker arms working loose. After the above procedure, I never had a problem again!
This Person is Correct. As he said if you are going to use Poly Locks then have the rocker studs machined flat so the Allen screw has something to go down to with even pressure.
But as others have mentioned. I used the GM Long slot rockers with there new nuts and did not have a problem. Now granted they are not designed to be adjusted many times as there factory crimp will get loose on the stud then you would need to purchase a new set of rocker arm nuts. But get GM. Happy Rocking lol
