Kay,
I can't imagine it's that different, but in gasser helicopters rich tunes always result in sharp wagging tails, as the engine is leaned out to a desired level, the tail settles.
Regarding the Max Head speed limit, I believe the Wiki calls for setting it to the maximum you want to run the rpm for your heli. This way, 100% of a flat throttle curve results in your maximum head speed setting. Same logic is applied for reduced percentages 60%, 70%. 80% etc. All result in easily calculated head speeds. If you define that as scaling, okay. When the Max Head Speed is set to high, and the governor can't attain it, that's when unexpected results happen i.e. full throttle output even though a flat curve is set to something other than 100%.
search for Automotive Stethoscope, here is a link to one that I found:
https://www.amazon.com/Powerbuilt-64058 ... B004KEHGZYNow that you seem to have the governor working, it's a good time to plan out how you are going to tune it. Before you tune the gov though, the engine should be broken in well enough that you can tune it so that it isn't overly rich. Governors don't like to govern engines that don't respond well.
I found that using the real-time tuning was a great time saver and made it easy to observe the setting differences. Set Governor Response and Holding Performance to F:Channels. I assigned them to dials on the radio. While flying, follow the Spirit tuning guides in the Wiki. In one flight the governor can be tuned. It's an awesome feature. Though Holding Limit cannot be set through F: Channel, that isn't as critical and you can tweak that each time you land, until overspeeding is minimal or acceptable to you.
Good luck as you progress.