I have a 1998 Ficht 115 and have been experimenting with various propellers. All the aluminum props were 3-blade:
19" aluminum (cloverleaf blades) - high top speed at 47mph and it gave low rpm cruising but WOT was only 5100, too low for this engine. Holeshot was terrible. I would never try towing skiiers with this prop.
19" aluminum (swept blades) - lost the top end but holeshot was still terrible. WOT RPM might have been a little more than 5100. This prop gets the "most useless" award.
17" aluminum (swept blades) - holeshot was noticably better and the WOT rpm went up to 5600. Top speed was reduced slightly to 46mph. This one gave the best overall performance of the three aluminum props.
17" SS Rogue (4-blade) - wow is this sucker heavy. Holeshot even better than the 17" aluminum. Gets on a plane at lower speeds than any other prop. Acceleration improved at all speeds. WOT rpm is the same as the 17" aluminum at 5600 rpm. Top speed increased slightly to 47mph, more or less equalling the 19" cloverleaf aluminum, but all cruising velocities showed an increase of about 500 rpm over that 19" aluminum. Best overall prop so far (it ought to be for the price).
The only negative is the slightly higher rpm at cruise, even compared to the 17" aluminum. I don't have exact figures for cruise rpm yet.
I'm going to keep the Rogue as my all-purpose propeller but would like to get another SS prop for cruising on a large lake, one that will have slightly longer legs but keep the 5600 rpm at WOT - i.e. have a slightly higher top speed. I've read the same pitch Viper and Rogue have similar WOT rpm numbers. Would the Viper accomplish the higher cruising speed? If not, would another prop do this while keeping the revs?
19" aluminum (cloverleaf blades) - high top speed at 47mph and it gave low rpm cruising but WOT was only 5100, too low for this engine. Holeshot was terrible. I would never try towing skiiers with this prop.
19" aluminum (swept blades) - lost the top end but holeshot was still terrible. WOT RPM might have been a little more than 5100. This prop gets the "most useless" award.
17" aluminum (swept blades) - holeshot was noticably better and the WOT rpm went up to 5600. Top speed was reduced slightly to 46mph. This one gave the best overall performance of the three aluminum props.
17" SS Rogue (4-blade) - wow is this sucker heavy. Holeshot even better than the 17" aluminum. Gets on a plane at lower speeds than any other prop. Acceleration improved at all speeds. WOT rpm is the same as the 17" aluminum at 5600 rpm. Top speed increased slightly to 47mph, more or less equalling the 19" cloverleaf aluminum, but all cruising velocities showed an increase of about 500 rpm over that 19" aluminum. Best overall prop so far (it ought to be for the price).
The only negative is the slightly higher rpm at cruise, even compared to the 17" aluminum. I don't have exact figures for cruise rpm yet.
I'm going to keep the Rogue as my all-purpose propeller but would like to get another SS prop for cruising on a large lake, one that will have slightly longer legs but keep the 5600 rpm at WOT - i.e. have a slightly higher top speed. I've read the same pitch Viper and Rogue have similar WOT rpm numbers. Would the Viper accomplish the higher cruising speed? If not, would another prop do this while keeping the revs?