I have a 1984 Sunrunner 245 with the GM 350 ( 5.7) engine and
alpha drive. I currently turn a 5.25 x 17 aluminum Solas prop. My tach is unreliable, but right now it shows about 4200 r.p.m. WOT. Next time, it may show 5000 rpm. It just doesn't have quite the speed I am looking for, at
approx 40...