Another vote for Diablo. The nose-high test is as close to infallible as you can get. For my first run of the day, I normally pump just a couple ounces into the tank, start the engine and let it rev for a minute or two to get the heat up, then hold it straight up at WOT. If I am holding the plane back from flying out of my hands, then I know I have all the thrust I need. I give it 30 seconds nose-high. When you point the nose up, the rpm's should increase because of the leaner fuel delivery, then they should stay high until you lower the nose again. If you hear a falling note with the nose up, bring it down and richen a click or two. When you've got it right, then fill the tank and fly with confidence.

This is setting the needle for a good compromise between power and reliability, with the reliability foremost.

I use the tach mainly for breaking in and tuning a new engine, evaluating a change of prop/fuel/plug, or after an engine has been broken down and cleaned. I like to see a reading between 10-11,000 rpm at WOT with the needle on the rich side of peak (this is for my two-strokes up to 90 sized).

I use the pinch test as well, for a ball-park indication of needle setting on an engine I have not been running on a regular basis--typically a new engine, or when helping someone get their engine set up.