[turtle1hp]

Hey guys!

I am working on the installation of my Ranger roller, BP7 regrind, for my recently ported head. 

I have been going through the different posts searching for information regarding the proper way to set up the valve lengths and the shimming of the HLA's on my head. During the search, I ran across multiple references indicating that by shortening the length of the valve, that the change in the rocker geometry will increase the TVL. (Total Valve Lift)

My questions are;
1) what would be the limit that you could do this? (I understand that there are different clearances that will need to be checked. Example: Rocker to retainer, retainer to seal, spring pressures or coil bind,  etc...)
2) what would the negative side effects from doing this?  (example: advancing/retarding the cam or possibly altering the opening and closing ramps of the lobes, excessive side thrust on the valve stem or HLA)

Even the minimal addition of .020"-.030"  should be of some benefit.  If I could get more, then I will take it.

[TurboRay]

.
Any small benefit you might gain from .010-.020 increase in valve lift due to shortening the valve stem will be far outweighed by the negative impact of increased guide wear due to side-loading, AND the potential for both follower-to-retainer interference and HLA breakage. 

If you want increased lift &/or other improved timing events.......get a performance cam. If you can't afford the 500-600 ish bux for a roller cam and followers, get an Engle "TCS-55" or "TCS-111" slider cam and use the correct "old-school oil" to prevent wiping it out. Both have proven to be good cams for Lima turbo applications. My 2¢......  <shrug>