450 Cam Mod Shims ??

2 replies to this topic
  • Chills

Posted January 15, 2005 - 10:56 AM


Have any of you had to use 200 shims when doing this mod? Just wanted to know....

When I first measured the clearance, I calculated having to use 195 shims, but once I actually got everything COMPLETELY installed, the clearance is out of spec: Too LOOSE...

Its not by much but definately out of spec......

Any thoughts??

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  • yz_for_me

Posted January 15, 2005 - 11:23 AM


What size were your shims before the cam mod? Were the clearances in spec before you did the mod? I think most people find they need a .1 to .2 mm thicker shim if their valves were in spec before the mod. When I did mine, I went from 175's to 190's which is .15 mm thicker.

  • Chills

Posted January 15, 2005 - 11:38 AM


One shim was 181, and the other was 186, My Initial check of the clearances were .358 and .330 respectively. So in doing the math, a 195 shim for both would get you within specs. But after installing the new shims, The clearance is .254 and .279 respectively. The shim that now measures .254 is slightly loose, but not loose enough to get the .279 in. And the shim with .279, is slightly loose also, but not loose enough to get the next guage in which is .305....

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