yt lifter preload?
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12 Second Club
Joined: Oct 2003
Posts: 146
Likes: 11
From: Mpls. Mn.
yt lifter preload? Hey all,
I just finished putting in yella terra 1.8's, patriot dual golds, and hardened 7.400" pushrods. My question is two-fold, when I put in the rockers without the shims, it seemed like the springs were being compressed under torque, and in fact bled down both lifters on the first cyl. I tried them on, so I surmised it must want the shims, and added them on all arms. Upon initial start-up, the two lifters that had bled down ticked loudly until warmed up, then quieted down. I dont hear any valvetrain clatter to speak of, but there is a different sound than before, kind of like a hushed tick, like a sewing machine in a distant room-certainly nothing I cant live with. Is that sound from too little lifter preload? or a normal sound from roller rockers? Am I better off leaving well-enough alone, am I going to lose lift from under loaded lifters? Or do I try it minus the shims? The second part of the question is do certain years need shims i.e. 98's, or is it on a case by case basis, the guy from yella terra said "maybe 10%" of engines require shims , and I was wondering if that meant from a certain year. any input would, as always be greatly appreciated.
I just finished putting in yella terra 1.8's, patriot dual golds, and hardened 7.400" pushrods. My question is two-fold, when I put in the rockers without the shims, it seemed like the springs were being compressed under torque, and in fact bled down both lifters on the first cyl. I tried them on, so I surmised it must want the shims, and added them on all arms. Upon initial start-up, the two lifters that had bled down ticked loudly until warmed up, then quieted down. I dont hear any valvetrain clatter to speak of, but there is a different sound than before, kind of like a hushed tick, like a sewing machine in a distant room-certainly nothing I cant live with. Is that sound from too little lifter preload? or a normal sound from roller rockers? Am I better off leaving well-enough alone, am I going to lose lift from under loaded lifters? Or do I try it minus the shims? The second part of the question is do certain years need shims i.e. 98's, or is it on a case by case basis, the guy from yella terra said "maybe 10%" of engines require shims , and I was wondering if that meant from a certain year. any input would, as always be greatly appreciated.
The shims are used to adjust the wipe pattern only, not for preload. The instructions suck, and LS1howto is wrong as well. You need to verify the wipe pattern first, then once that is done measure for pushrod length.
Despite what most think, these are not simply bolted in place, you need to take the time to correctly set them up.
Here is how I set my wipe pattern: Link
Despite what most think, these are not simply bolted in place, you need to take the time to correctly set them up.
Here is how I set my wipe pattern: Link
11 Second Club
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Joined: Jul 2005
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From: Daytona Beach, Fl / Stuart, Fl
What he said. You could have to long of a pushrod. Put on of the cylinders at TDC, that way you came be sure that both valves are closed. You should be able to push on the rocker on the pushrod side and it should feel a bit springy
