what could happen if valve lash isnt set correctly?
#1
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i've wondered this since I replaced my slightly bent pushrods last year, as we finished up it was totally dark outside, we could hardly see, and were getting tired of cutting up our hands, so we just went through the rockers and torqued them down once at 22ft lbs, we didnt turn the engine over, but I made sure that the rockers did seat and that they were centered over the pushrod and valve.
how bad was that? since I trap 103mph with my current mods, i've always figured my ls1 is slow for some reason, and possibly this has something to do with it?
I really know nothing about valve lash, its the amount of dead play with the cam lobe away from the pushrod and the clearance needed to open the valve right?
I never understood it, and this is just what I thought- someone help out the ignorant please!
how bad was that? since I trap 103mph with my current mods, i've always figured my ls1 is slow for some reason, and possibly this has something to do with it?
I really know nothing about valve lash, its the amount of dead play with the cam lobe away from the pushrod and the clearance needed to open the valve right?
I never understood it, and this is just what I thought- someone help out the ignorant please!
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A hydraulic cam should never have "lash," instead you have a certain amount of preload on the lifter. Lash only comes into play with solid camshafts.
That being said, if you reassembled with all stock spec components, there is no need to do anything other than tighten the rockers down to the correct torque setting. The torque setting on the rocker is to ensure that the rockers are securely attached and will not fall off, not to determine preload. The stock LS1 valvetrain is not adjustable, nor should it need to be adjusted with stock heads/valves/pushrod lengths.
That being said, if you reassembled with all stock spec components, there is no need to do anything other than tighten the rockers down to the correct torque setting. The torque setting on the rocker is to ensure that the rockers are securely attached and will not fall off, not to determine preload. The stock LS1 valvetrain is not adjustable, nor should it need to be adjusted with stock heads/valves/pushrod lengths.
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Hey my Olds motor HAD non adjustable valvetrain, oh, nevermind, this is an LS1 page <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
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</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by CutlassRacer:
<strong>Hey my Olds motor HAD non adjustable valvetrain, oh, nevermind, this is an LS1 page <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Rocket motors don't count! <img border="0" alt="[jester]" title="" src="graemlins/gr_jest.gif" />
<strong>Hey my Olds motor HAD non adjustable valvetrain, oh, nevermind, this is an LS1 page <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Rocket motors don't count! <img border="0" alt="[jester]" title="" src="graemlins/gr_jest.gif" />
#6
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George is right ....
BTW, Turbo Buicks (GNs / TTA) dont have adjustable valves either. Same deal as the LS1.
BTW, Turbo Buicks (GNs / TTA) dont have adjustable valves either. Same deal as the LS1.
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The LS1-style motors are the ONLY ones like this, so consider yourself lucky. On LT1’s and almost any other engine the valves have to be adjusted anytime the rocker nut is loosened.