Was that a Pro Zinger or just standard Zinger?
I found this thrust VS RPM chart on Zinger's website. I think this it's generic. Not all props are identical. Even the Zinger and Pro Zinger of the same pitch and diameter turn different RPMs on the same engine. The Zinger is lower. I didn't even know Zinger had props this low in pitch at 20 inch diameter. Cool.
http://www.zingerpropeller.com/Thrust.htm
ORIGINAL: seanychen
I tried a Zinger 20x6 w/ 5% Omega fuel. It peaked at 7500 rpm. Very good transition, and a lot of thrust, so much it's hard for me to hang on to the plane. I'd say at least 20 lb. of static thrust.