I have a J3-C with an A75-8 engine. It has steel prop that measures 74 inches. At cruise I get around 2200 rpm's which makes me think I have the wrong prop because the A75 is supposed to turn 2400 or so. However, Wag shows a steel prop for an A65 at 74 inches an a wooden prop at 72 inches. I'm confused. What is the correct prop - both steel and wooden? Thanks in advance.