Gearing - Boost vs No Boost

[/tobys]

What are people doing with their gearing as a general rule of thumb when adding boost to their speedo setup? Is there a general rule that would say, "gear down 2 pinions" (as an example)?

Cheers

[samd]

Dex410 6.5 X12

21tooth no boost, 170degF motor temp

19tooth 15deg total boost, 145degF motor temp

Same speed, maybe a little faster boosted

[RogerM]

Toby, still experimenting but at the moment I am using 1 tooth per 10deg of boost as a rule of thumb and not getting any silly temps or other issues.