rocker arm adjustment
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rocker arm adjustment
Ok so I am noticing that people are not even following the firing order when they are tighting down the rocker arm. Some are just tighting it down to 22ft lbs. How are they getting by with this? Even on ls1howto, on there cam and valvespring swap all they say is to tighten them down to 22ft lbs. From what I have always done on past motors is bring the pistion of that cylinder to tdc and adjust the valves right?
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There is a GM service procedure. However, I just start tightening them, and any that are on cam lobes I dont do. Once I get them all done, I roll the motor over and catch the ones I missed on the first round. Then I roll the motor over a few more times and go over each of them at least once or twice more.
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While it isn't the proper procedure, tightening the rockers down while not on TDC for that cyl most likely isn't going to hurt anything. Proper procedure is to ensure each cylinder you are tightening is on TDC.
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What are you worried about? I'm assuming you still have the hyd roller lifters. Tighten them down and slap it on the *** and let er eat. If the lifter is full of oil you'll open the valve a little if its not you'll compress the spring in the lifter. when you start it oil will flow and all will be good.
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If you just arbitrarily tighten them down, then 22 ft-lbs is not 22 ft_lbs. Torque the exhaust when the intake begins to close, torque the intake when the exhaust begins to open. This is a standard technique to ensure that you are on the base circle.
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Yea lol I know how to adjust the valves. I have done it plenty. I just don't see how people are getting by with torqing them down 22 ft lbs and takin off. I would think you would have some serious problems.
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What problems would you have. Watch when you torque it down, it will compress the lifter or open the valve a little, I am assuming correct pushrod length. As soon as you fire it up oil will flow. The full lifters bleed off and the valve closes the empty ones will fill and smooth everything out. Torque em down
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you should tighten them down on the base circle of the valve you are working on...
also, dont just crank down to 22ft lbs...
get it to zero lash first, then count the number of turns it takes to get to 22ft lbs.
1 full turn is .047 preload
you can then also see if you have the proper pushrod at the same time... too much preload, you need a shorter pushrod, too little and you need a longer one
the plunger is roughly .160 of travel total.
GM recommends .080~.100 for the stock setting
an aftermarket setup typically you want less preload than that,I usually shoot for .020~.040
also, dont just crank down to 22ft lbs...
get it to zero lash first, then count the number of turns it takes to get to 22ft lbs.
1 full turn is .047 preload
you can then also see if you have the proper pushrod at the same time... too much preload, you need a shorter pushrod, too little and you need a longer one
the plunger is roughly .160 of travel total.
GM recommends .080~.100 for the stock setting
an aftermarket setup typically you want less preload than that,I usually shoot for .020~.040