Valve timing and lift will change clearance but a minimum clearance spec at any given time can be targeted
As far as what that number should be CAN be a matter of opinion but as a rule of thumb if a piston is chasing a valve closed I like to see a bit more clearance there as possible valve float delays closure which in hand reduces clearance at that point in time, Yeah I know ya should spring it to control the valves just a small built in safety factor
Conversely if a valve opening is chasing a piston away from TDC you can live with a touch less clearance
__________________
........... The More You Follow The Herd The Less You Can Be In The Lead ..........
|