Bushing-Style Roller Lifters

[carl hinkson]

There are a lot of shops and guys who never measure lifters for size and so on the ISKY its taken 2 if not 3 sets to make up one set to get the sizing correct,

ISKY .842 lifter are never .842 but from what I have measured are .8405 to .841 and GM lifter bores are .844 and .003 to .0035 clearance is to much and lifter will not live in that condition, The Durathon will be .842 as this are made by Morel.

Go to yellow bullet and do a search as there are a a lot of threads on sizing problems with ISKY lifters.

I am one of those guys that measures every lifter for size before any work is done to the lifter bores.

On bushed lifters since they have been out I have gotten calls about failed bushing lifters no certain brand but they have failed.

So far I have gone to all .904 lifters on my builds and blocks I sell I machine alot of .904 lifter and to date whether its an ISKY or Morel I have seen zero problems.

I am have been machining a few blocks for the .937 Morel lifters and those are a bushed lifter and no problems as of yet but still to new to say anything.

One area people never look at is pressure angle
http://performancetechnician.com/pdf...a-Lifter-2.pdf

I machine alot of 55MM cam tunnels and I always go to a .904 or .937 lifter with a .810 or .850 wheel to slow wheel speed down less revolutions around the lobe which is key.

Good discussion on bushing lifters
http://speedtalk.com/forum/viewtopic.php?f=1&t=41853