1976 75hp Johnson Stinger prop

[catfish76058]

I am thinking of changing my prop on my boat. It's an old one and the prop is worn some but it still does ok, but it's sort of slow. I currently have a 13 3/4 x 15 - 13 spline and I'm wondering what I need to upgrade to to increase my speed. this is an old motor and I dont think I can put a larger prop on it but I don't know about pitch and what is faster or slower. I sure hope someone can help me with this. Thanks in advance
Jay

[lk2ds0n]

I'm brand new to this myself, but I just had this explained to me yesterday. If I have this wrong someone please correct me. I claim to be no expert. I'll share with you what was just shared with me yesterday.

The pitch has to do with the distance the propeller travels horizontally for one complete revolution of the propeller (measured in inches I believe). So a 19 pitch propeller would travel 19 inches horizontally in one revolution. The higher the pitch number = the further the propeller travels per revolution = the faster the boat would potentially travel.

The draw back of a high pitch propeller is that, while the boat will have a higher top speed, it will provide less low end torque for pulling skiers up out of the water.

It was explained to me that you could put a lower pitch propeller on say a 30 horse motor... and get skiers up easily. On the other hand you could have too high of a pitch propeller on a 100 horse motor and struggle getting skiers up. Depending on what motor you have, you'll need to more or less find that sweet spot for what it is that you want to do.

I'd suggest to call around to several boat shops and get a consensus opinion from several folks who see this experience every day before I'd spend the money on a propeller that wasn't quite ideal.

I wish you the best of luck!