LT1-LT4 Modifications 1993-97 Gen II Small Block V8

roller rocker adjustment

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Old 07-12-2009, 02:13 PM
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Default roller rocker adjustment

How do you adjust roller rockers on an lt1? Mine doesn't seem right. I don't know what brand the rockers are. They are blue and say 3/8" 1.6 LG on them. When I try to adjust them, the locknut bottoms out just about when they get to zero lash. Is that normal or do I have the wrong length pushrods in it. The reason for me adjusting them was because of valvetrain noise at startup that goes away once it is warm. So I thought the rockers needed to be a little tighter. Thanks

Ryan
Old 07-12-2009, 03:29 PM
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ttt. How about any other brands of rokers? aren't they supposed to go to zero lash then 3/4 turn more?
Old 07-12-2009, 04:28 PM
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http://shbox.com/1/4th_gen_tech2.html#adjust_valves
Old 07-12-2009, 05:11 PM
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Originally Posted by 25thhawk
ttt. How about any other brands of rokers? aren't they supposed to go to zero lash then 3/4 turn more?
It has nothing to do with the rockers. It's strictly a parameter of the valve lifter. Most lifters like around 1/2 turn past "zero" lash, but the OE rockers, can tolerate up to 1 full turn. The Comp 875Rs, however, need to only have 1/8 turn.

Secondly, roller rockers don't have traditional "locknuts". They have what is called a "polylock", which is a hex headed adjusting nut that has a socket headed "locking screw" in it's center. You back out the set screw in the center of the hex nut, set your valve lash, then turn down the set screw to "lock" the hex nut, while holding the hex nut in position. This holds the valve lash setting.
Old 07-12-2009, 05:15 PM
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Originally Posted by leadfoot4
. You back out the set screw in the center of the hex nut, set your valve lash, then turn down the set screw to "lock" the hex nut, while holding the hex nut in position. This holds the valve lash setting.
I turn the whole assembly another 1/16th of a turn to lock in the lash after I have set the lash. it seems to keep the locks from backing off
Old 07-12-2009, 08:38 PM
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Thanks guys, I figured out the whole set screw thing once I had one off of the car. Mine seemed to like 3/4 of a turn. 1/2 turn still made noise during startup and for maybe 30 seconds after. 3/4 made no noise during startup. Ill have to see in the morning when it is cold how it works. Thanks

Ryan
Old 07-12-2009, 10:15 PM
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EOIC

http://www.youtube.com/watch?v=VPOaAsuzhsE
Old 07-12-2009, 10:25 PM
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Well there ya go...
Old 07-13-2009, 05:40 AM
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Originally Posted by 1redta
I turn the whole assembly another 1/16th of a turn to lock in the lash after I have set the lash. it seems to keep the locks from backing off
I understand what you're saying, however, you have to keep in mind that extra 1/16 turn, while slight, does add pre-load. I've used the ARP poly-locks on a couple of engines, and they recommend torquing the set screws to 22 lb/ft.
Old 07-13-2009, 11:56 AM
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blue rockers...prolly scorpians or proforms but I think scorpians have a little scorpian on them so most likely proforms
Old 07-13-2009, 12:48 PM
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So when you dont know what type rockers you have, whats the best way to adjust em?
Old 07-13-2009, 03:21 PM
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Originally Posted by SlideRight
So when you dont know what type rockers you have, whats the best way to adjust em?
it doesnt matter what brand of rocker you have. just find zero lash, and add preload to the specs that your lifters need
Old 07-13-2009, 04:59 PM
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Originally Posted by ThreeHonks
It doesn't matter what brand of rocker you have. Just find zero lash, and add preload to the specs that your lifters need
As also mentioned in post #4.....



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