i have a 23ft 1980 wellcraft with a bb 454 and an alpha 1 out drive .is it normal for the rpm to match the mph? IF not what can cause that problem THANKS
Be careful with that engine and drive. That engine will crush that outdrive if you use it hard. To much torque for that outdrive to handle, later 454's came with the heavier drives. Keep the holeshots to a minimum. A friend of mine exploded the outdrive in his and I've heard of a lot of others with the same problem.
man of war, in almost every boat I have ridden in, MPH = RPM up to a certain point. In my boat, it's accurate until you reach WOT & start to trim up the outdrive. Then MPH goes up more than RPM
I can only wish RPM = MPH with my little 2.0L Volvo AQ130C! At sea level, I'm doing 28-29 mph at 4400 RPM. At WOT (5000 RPM), I'm doing about 32 mph, but I don't keep it there for long.
Apologize for earlier post, my girlfriend is a wise a$$. Of the three boats I have owned [2 Chriscrafts,1 Sea Ray]. The 2 Chriscraft's were exactly 100 rpm = 1 mph. They were both 260 mercs. The Sea Ray is only 188 & doesn't get near that.I believe that an alpha is only rated for 300 hp, so wvit100's giving you some good advice..........J
