Carb sync? Never again.

[kitfox2009]

Sorry Jim
That probably didn't answer your question. Not sure if you would call that "testing".So take this idea and results as a very seat of your pants summary. It may not help at all.
The flight training was a lot of fun though,especially for an ole guy.
Cheers
Don

[mr bill]

The Hal Stockman cross over tube conversion is done and it works as others have said. I added 1/8 NPT hole to install a nipple for CarbMate pneumatic sync. I also used a one inch coolant hose across the manifolds. I did the mechanical sync as carefully as I could and when the CarbMate was hooked up, the carbs were in the green at 3500 rpm and at idle with no further adjustment needed. The rough spot between 2500 and 3500 rpm is gone.