Thanks for the help. I was inspecting everything while moving the batteries to just behind the firewall to over come tail heavy problem when I found that the insulation was worn off the wire to the Hall's sensor where it was rubbing on the metal standoff mount. I think I found the cause of my miss. Why did it run fine on the ground and only start to miss while airborne. Murphy Law. I made careful use of tie wraps to make sure this does not happen again. Went by the local hobby shop to get some small stuff and saw that the price of glow fuel was $32 per gallon. I knew there was a reason for going through all this trouble getting the gas engine installed and sorted out. I've ordered a 17-6 prop and will see how that works. Maybe not until spring unless the skis I ordered for the plane get here. Snow today, more snow on Friday and then more on Sunday. Maybe I should move south.