SR20DET Engine Rebuild – Checking Valve Shim Heights – Help Prevent Uneven Cam Wear and Rocker Throwing Problems like Breaking Rockers or Throwing Rockers Off or Throwing Shims Out , Now what we got here is a dial indicator on an old lifter with a dial indicator shaft in it what we're going to do is we're now going to check these heights just in case you guys have messed them up or took them out and didn't take the sequence down so now we'll put the shim guide and the shim itself and we'll now put it in dial indicator okay what we're going to do is we're now going to zero out our dial indicator okay now what we're gonna do is we're gonna we need these to be within one thousandths of an inch of each other if they're not it'll cause uneven cam wear and may also cause you to have rocker throwing problems like breaking rockers or throwing rockers off or throwing shims out so what we want to do is now we'll pick this up carry this over to the other one and we will see that we were that we are now within a thousandth of an inch between the two now what we got here is a dial indicator on an old lifter with a dial indicator shaft in it what we're going to do is we're now going to check these heights just in case you guys have messed them up or took them out and didn't take the sequence down so now we'll put the shim guide and the shim itself and we'll now put it in dial indicator okay what we're going to do is we're now going to zero out our dial indicator okay now what we're gonna do is we're gonna we need these to be within one thousandths of an inch of each other if they're not it'll cause uneven cam wear and may also cause you to have rocker throwing problems like breaking rockers or throwing rockers off or throwing shims out so what we want to do is now we'll pick this up carry this over to the other one and we will see that we were that we are now within a thousandth of an inch between the two