|
Hello John,
No, in this case he is talking about the total expansion of the valve in relation to the guide clearance. The issue we are discussing is whether the heat of combustion causes the valve stem to expand enough so that the actual clearance when running is smaller than the cold clearance adjustment. My experience with measuring hot clearances suggests not. Most of the other engines I know have higher clearances for exhaust valves, in the 911 that is not the case, and may have more to do with the expansion rate of the aluminum, not the steel valve.
I can't really understand what your chart is saying, both lines look brown to me. Can you give me a hint ?
__________________
Paul
|