high speed mixture settings using digital tach

[ScreaminXP]

What is the best (most precise) way to get my high speed mixture dialed in using the digital tach? I thought this would be more accurate than just reading plugs for a shade of brown. I thought there was some way using a tach..like 1/8 turn increments richer until you drop rpms, then back in 1/8 turn. Is this accurate, or should I go leaner until I get max rpms, then richen a bit from there? (then check the plugs for a second opinion?)

[Bryan Glynn]

Lean it out, until the RPMs start to drop at all - then richen until they can be sustained...I would personally then go a 1/16 richer for a safety margin.

[ScreaminXP]

Thanks Bryan. Will keep an eye on the tach for any drop off then richen from there.