No experience with digitals but I spent almost half a day attempting to get analog servos to return engines to the same 5,000 rpm high idle setting. With some disappointment I finally settled on a 5,000 to 6,000 rpm high idle range. The experiment had nothing to do with Twinsync but was for engine out simulation.

Conclusion was that analog servo return to position was not very accurate. The spring preload barrel rotation and short throttle rotation arm does not help accurate control of engine rpm at idle setting.

After taking a second look the carburetor barrel rotation will vary between engines from about 50 degrees to about 70 degrees. Most servos will rotate 90 degrees at 100%. A longer throttle barrel rotation arm and 140% travel (or maximum) using all the servo rotation should assist Twinsync in more accurate speed control with any servo. The change will probably also help my initial return to same rpm problem.

Bill