What causes a collapsed lifter???
yea, I figured the solid lifter, thanx though. As far as preload goes, I am using the engine running method and 1/4 turn preload. Is it possible to collapse the lifter with too much or too little preload?
On The Tree
Joined: Oct 2006
Posts: 125
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From: Metairie, La.
I just bought pro mag 1305's from Lopers speed on ebay. $250 including shipping. Best price I could find new, if your looking to go that route.
Last edited by rickreeves1; Feb 18, 2009 at 05:28 AM.
Several years ago, I thought I had a stock lifter getting a little noisy, so I put in a new set. I had the time, while the car was down for the winter. being a "performance oriented" guy, I got a set of the CompCams 875R lifters, 'cause they were supposed to be a "performance upgrade".
The instructions said 1/8 turn of preload, but at that setting, they were a little noisy. So, I set them at 1/4 turn. A while later, I had another question come up, so I called CompCams tech line, and while discussing the original question, I brought up the preload setting for the 875Rs.
Their tech rep was very concerned that I didn't follow their instructions, and he explained why their lifters required only 1/8 turn of preload, and yes, their design is such that they are inherently a little noiser that OE lifters.
But, going back to the LS-7 lifters, they were originally designed for the LS series of engines, which don't really have any adjustment, at least from the factory. Also, there have been a few discussions here, as to whether the LS7's plunger sits a little lower in the lifter body, creating a "shorter" lifter. If so, that might call for longer pushrods, as well as a different preload.
Yea, i am kinda concerned with getting the right pushrod length. I made a solid lifter last night and in order to get the proper wear pattern on my valvestem i had to go as short as 7.000". I am assuming that the reason for such short PR is because I had to have my heads milled in order to straighten them out (the previous owner took a wire wheel to them to remove the old gasket and put all kinds of divots in the heads). That combined with me using a felpro gasket instead of a stocker. I am concerned because with the particular rocker that I'm using, if the lifter is shorter, I may run into trouble with the rocker hitting on the base of my rocker studs.
