4 vs. 3 blade propellers, which brands are better?

[walleyehed]

Re: 4 vs. 3 blade propellers, which brands are better?

In fact, most sterndrives will not benefit at all from a vented prop- it just doesn't need the extra slip. <br />

Better do a bit more research on that...<br />Thru-hull is the only one of the sterndrives this doesn't work on, as you mentioned.....refered to as "Thru-transom exhaust"

 

[stevens]

Re: 4 vs. 3 blade propellers, which brands are better?

Here's a link to that torque curve again, only bigger:<br /><br /> Torque chart <br /><br />The curve starts at 1800 rpm, peaks at almost 200 Ft/Lbs at 2000 rpm, and only decreases from there. Obviously, the turbo kicks in at very low rpms.<br /><br />The boat does about 20 knots at 3100 rpm, which seems like a pleasant speed to go at even for the kids. At that speed, I burn about 2,6 gallons of fuel per hour. The higher pitched prop should bring both RPM and consumption down a bit too, I think.<br /><br />Anyway, the current Ballistic prop is vented and I can feel it spin when I first hit the throttle. Then, after a second or so, it will gain in grip and we'll start to accellerate.<br /><br />The prop that originally came with the boat (the Black Max) was not vented either. I'll just put the Turbo prop on on Monday and see how it goes.<br /><br />Edit: follow-up in this post:<br /><br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=012718