I ran a couple of tests over three months apart with the plane (RV-6A) in the long range race configuration to determine a top speed that can be compared with a new prop in exactly the same configuration. In July at 6,000 ft density altitude and everything maxed out for speed I got 176.0. Today without toping the tanks again I ran the same test and calculated 177.5. So the average is 176.8. Without changing anything except the prop I will someday run the same test again and report the results. Let's hope it is 3 kts faster.
Bob Axsom
Bob Axsom