Whirlwind prop performance

[runstrong92]

I've been running a Sterba 68x74 on my 160hp RV-4 but will soon be swapping over to a GA200L from Whirlwind. Just curious what kind of performance increases have been seen by others who have made a similar swap.

 

[judoka5051]

Get ready for a big gain!

It will take a little fiddling, but once you have it dialed in... In my case I swapped from a sensenich cruise prop to the whirlwind. The plane cruised a little faster and climbed like crazy. Start with the coarsest pitch on the chart. I ended up going 1.5 coarser to get 2700 at 9000ft.