ORIGINAL: Flyer Freq
In analyzing this, in regard to vertical performance, if I was level and at or near full speed, and I pulled straight up, she would climb out of site. If I am vertical, and cut my throttle to halt my climb, and then add throttle to maintain altitude, the engine dies, If I then go back to idle, quickly, the engine remains running. I drop my nose then, and give her the gun in level flight and we are back off to the races, tearing through the sky like its tail is on fire. Weird and frustrating!
I don't know if you were one of those who drilled out the pressure nipple on your muffler or not but those who do this should be aware that doing so can often have a very negative effect.
What is sometimes forgotten is that there's no check-valve in the pressure line so the bigger the hole in the pressure nipple, the quicker the pressure in the tank can bleed OUT once you cut back to a lower throttle setting.
If the hole is to big, this can produce major transition problems.
Here's the scenario ---
You are running at full throttle so the tank build up a steady pressure.
You cut throttle back to a lower setting and the engine continues to run -- but the pressure in the tank now reduces because the tank-pressure is now higher than the muffler pressure so the flow in the pressure line reverses.
You hit the throttle again and suddenly the engine is trying to run at full-throttle RPMs with just a fraction of the pressure it normally has at those throttle settings -- because the tank has yet to repressurize.
I've had quite a bit of success in "taming" badly behaved engines (which won't transition for ****e) by varying the size of the pressure nipple. Sometimes less is more, especially in 3D stuff where you're more interested in sustaining a constant tank pressure during pretty regular and frequent throttle variations.