ORIGINAL: proptop
FWIW, today a friend and I tested a Saito .90 twin on 15% Powermaster, then 30% Cool Power (with 4oz. Castor added ) and noticed a gain of 400 r.p.m. when peaked.
It went from 9,900 max on 15% to 10,300 on 30% with an APC 13X7
What plug or plugs did you use?