Quote:
Originally Posted by kevin.ri
I Just put on a Brand new 150 Etec on my '73 20sf and I too am having trouble getting past 5100 but I took the prop off my old 150Di which is 14.5x19... I plan on pitching down. Quiet honesty I'm torn between which prop to get.
|
Most dealers seem to mount motors too low, so before you change props check height of AV plate above bottom. Capt. Terry is running a 150 HO E-TEC on his Seafari with AV Plate at 1.5" above bottom and that puts it on top of water where it should be when he's up on plane. If motor is too low, the extra drag will cost you some rpm.
However I think 19" pitch is still too much for a 3B prop. If it's an aluminum prop, a good shop could repitch it get more rpm. What specific prop are you currently running, and what is the most important characteristic you want in a new prop? (i.e., bow lift for maximum WOT speed, stern lift to be able to hang on plane at lowest possible speed in rough conditions, hole shot for maximum acceleration when pulling skiers or carrying a heavy load, or maximum mpg at cruise?) There are different types of props that are optimized for a specific purpose, so you need to figure out what characteristic is most important to you. The Viper is BRP's bow lifting speed prop, but you may have trouble planing below 20 mph with it. The 3B Rebel has very large blades and is normally used on the bigger 3.3-3.4L motors; the 2.6L motor typically can't spin it fast enough on a 20' hull. The 4B Cyclone has lots of stern lift and should let you plane at ~12 mph, has a good hole shot and very good cruise mpg but may give up 2-3 mph on top end speed to the Viper. Both the Cyclone and Rebel are very heavily cupped so act like their pitch is much higher than advertised. I can only spin the 15P Cyclone to ~5400, but that's perfect for my motor which has an optimum RPM of 5300-5500. Optimum rpm on the newer 150's is more like 5500-5750.