16-8 APC 7650 tonite starting to wean it of regular oil. On stand it will idle down to 2140+/- and run smooth. I have not run it on the plane yet, hope it will sit still at that rpm. (US120)
I did remove the butterfly and soder the small vent hole closed, could not get it to die with throttle closed before, shuts down now.

Not familar with the jag muffler but would be interested in the preheat coils project esp. if you have some pics