<<...the way Ron explains it is the best way to go...>>

Not so much "the best", but definitely the most fool-proof way to assure a good throttle response. Just don't get locked into the 100% ATVs. As long as BOTH ATVs are the same and at least 70%-80%, you'll be okay. More is better, of course, since more ATV means better servo resolution. And don't be afraid to change the "size" of the box. If you cannot get the ATV rates you want with the balls on one particular hole, try another one.

A quick tip: it is generally best to use the outer hole on most OS throttle arms, and match the servo arm to that. Just remember that this is the ONLY area you have any "fudge factor". The pushrod length is dictated by the distance from the servo output shaft to the mixture screw. Since both engine and servo are permanently mounted, there is no adjustment available there.

I've been talking with a few folks about the "trapezoid" set-up and, like I suspected, there's more to it than meets the eye. This definitely is worth more research- after I finish the OTHER half-dozen projects I've got going on...<G>

Steve