ORIGINAL: Scar
One way to measure thrust is to secure the plane with a digital fish scale linked to the plane. Run the engine, see how much it pulls. Compare props, or fuel, or mufflers, or settings.
Good luck,
Dave Olson
thats my preffered method....just remember what the fish scale limit is.... trust me, a 50cc methanol twin on a 20 lb spadmaking 24lbs of thrust on a 15lb scale is terrifing when it chases you around your yard