<<...if you have equal throws on both sides of 90 degrees...>>

Ah; but will you have that with one arm longer than the other (trapezoid)?

By definition, a trapzoid is an equilateral with two parallel sides. To get ninety degrees at 50% servo throw/throttle opening, the servo arm and throttle arm must the two parallel sides. This means that the length of the actual pushrod will NOT be same as the distance from the servo screw to the center of the throttle arm; along with the longer servo arm, I don't see how you're going to get equal throw on each side of center. Going the other way (offsetting the servo arm, making the pushrod parallel to the plane from the servo screw to center of throttle arm) would be even worse, I think (that cosine effect Howard mentioned).

Does any of this matter? Good question. The first "trapezoid set-up" I just described above is what Bill Meador observed on Curtis' ship not long ago (for those of you who that matters to), so obviously it works to some degree.

All I know for sure is, after I began using the "boxed" throttle linkage set-up, all my throttle and engine response problems went away. This certainly isn't the only way to do it, but it is a way, and it works admirably if you take the time to do it right.

Pardon this comment; but discussions like this always remind of something the late, great Don Chapman said;

"Too many guys are trying to get the max out of their machines, when they should be concentrating on getting the first ten percent right."

I know, Hivoltage was not looking for the latest whiz-bang 3F trick; just some basic throttle set-up info. Many times, though, these discussions deteriorate into the esoteric, and the poor newbie who just wanted to know what to do is left shaking his head...

But no fair, Howard, about the servo overdrive thing. That was a cheap shot at we poor JR guys...<G>

Steve