>Ladies and gentlemen,
>I have set the gap between spinner and cowl to approximately .175"
all around. I'd like to close in this gap a bit with an additional
1BID on the face of the cowl. So, in everyone's opinion, how small a
gap would be too small and result in eventual contact due to engine sag?
Angier Ames
N4ZQ

That depends on your plan for correction after the engine sags.  If you have
put extra washers on the top that can be removed after the sag (a good
plan), you will end up with a net reduction of gap.  If you have no extra
washers on top, you will be putting extra washers on the bottom which will
increase the gap.  Your choice.   I was trying to end up with a .125 gap but
since I had to add washers, the gap is more like .25.
Bob Jude, N65BJ