just done 2 days racing where i cut 5 lash caps in half. they were brand new comp cams units so fatigue is not part of the equation. i recently installed new Manely valves on my -1's, with the new valves i added new Crower locks. since they were new valves i thought the new locks & lash caps would be the right thing to do. i'm now thinking either the Manley valves are shorter so the lash cap doesn't seat on the valve properly or that the Crower locks lash cap receiver groove sits slightly higher, but in any case we've concluded the lashcap is seated on the lock, not the valve & the 550lb spring pressure is acting like an axe & cutting the caps in half.
has any member here ever experianced anything like this. it's the same valves that do it everytime.

i don't think i've ever had that problem but it certainly has happened (cap hitting locks). when using lash caps you MUST closely and i mean closely inspect everything to make sure the cap is seating on the stem and not touching the locks. you need to recheck everything for clearance and it might also be a good idea to inspect the locks/valves of the ones you had the problems on, this is a disaster waiting to happen.

My opinion is you should not mix and match locks / keepers and lash caps
from different manufacturers. And there is different thicknesses and heights of the lash caps.

There are diffrent depths of locks and diffrent heights of the keepers,as weel as lock groove locations on valve that you must be carefull not to mismatch..We use lash caps on Hemis with 5/16 stems but only when necessary on 11/32 stems since there is so much more contact area.

I would measure the depth of the recess on the lash cap, and then the tip protruding from the lock. A quick check is with permanant marker on both bottom faces and sit it on the end of the valve. Quickly turn the lash cap before the marker ink dry and you should see pretty quickly as to what is touching what.
IHTH's

Most all caps are .080 thick,the recess skirts is the different depths.