Mercruiser Prop Diameter ? 14.5x19 vs. 15.3x19

[dhoffman]

I have a question on prop diameters. I have a 1993 Bayliner 2250/ Mercruiser 5.0LX / Alpha I Gen. II running a Solas Amita 14.8X17 3 blade at 5000 - 5100 rpm. I want to get down to the reccommented RPM range (I belive its 4600 max.?), so I am looking at the Solas Amita 19" props sold here. My question is: What would the difference be between the 14.5x19 & 15.3X19" 3 blade props. I have plenty of clearance for the 15.3X19. Just wondering about difference diameter makes(if any) for RPM, lift, speed, ect. Any help is appreciated.

 

[DJ]

Re: Mercruiser Prop Diameter ? 14.5x19 vs. 15.3x19

Typically, one inch of pitch equals two hundred RPM.

 

[dhoffman]

Re: Mercruiser Prop Diameter ? 14.5x19 vs. 15.3x19

I already found the info about the pitch, I was just wondering about the difference (if any) the diameter of the prop would make.<br />Thanks.

 

[Tail_Gunner]

Re: Mercruiser Prop Diameter ? 14.5x19 vs. 15.3x19

None perhap's walleyed or some other will come in and explain the diff, hub size doesnt determine how the blades push you thourgh the water.

 

[DJ]

Re: Mercruiser Prop Diameter ? 14.5x19 vs. 15.3x19

Larger diameter (usually blade length) will typically bite harder and hold better. Pitch is pitch. You obviously have the power to turn the larger diameter prop.<br /><br />You MAY sacrifice a little speed with larger diameter.

 

[walleyehed]

Re: Mercruiser Prop Diameter ? 14.5x19 vs. 15.3x19

Yes, for the prop you are looking at, it has an increase in blade area which is a better heavy load prop. The design itself may determine whether you lose any top-end.

 

[Texasmark]

Re: Mercruiser Prop Diameter ? 14.5x19 vs. 15.3x19

My 2c is that the larger blade, as the guys mentioned, bites harder and holds better. I see this as a reduction in slip.<br /><br />I did charts on my rig from just on plane to WOT and mine is a very light, fast-considering, boat. <br /><br />My slip went from about 35% at planing speed to about 8% at WOT. If I had a heavy deep V, or the like, there is absolutely no doubt in my mind that my slip would be larger.<br /><br />So, you put the larger diameter blade on the heavier righ to reduce the slip which improves mph.<br /><br />Otherwise I dunno.<br /><br />Mark

 

[dhoffman]

Re: Mercruiser Prop Diameter ? 14.5x19 vs. 15.3x19

Thanks for the answers guys. I didn't think the extra 3/4" diameter would make much difference. I'll go ahead and order the 15.3X19 to try.<br />Thanks again.