How much is too much

[pcope]

I ha e a 1976 tidecraft fish and ski 17 foot. The evinrude 115 is strong. Even with a boat full of people it planes in seconds. But I enjoy cruising and would love more top end and less rpm. 40mph is about it. I would love 50.

 

[Sea Rider]

What's your max rpm you alone and lightly loaded ?

Happy Boating

 

[pcope]

Have no tach unfortunetly.

 

[jbcurt00]

What's your max rpm you alone and lightly loaded ?

Happy Boating

Yep ^^^, and what diameter and pitch prop are you running now?

 

[pcope]

12 3/4 x 21

 

[Sea Rider]

Should start with an induction tach if wanting to gett the most out of that OB, although it's not rocket science dialing a prop, it's very close to it with a tach. Don't play with pitches blindly without one , could go lugging or over revving badly that nice OB.

Happy Boating

 

[pcope]

Roger that. Looks like its tach time

 

[jimmbo]

If your top speed is 40 mph with a 21, you are over propped, or your engine is in need of work. A 21 @ 5500 rpm would be close to 52 mph. At 4500 rpm, the bottom of the recommended range a 21 shows about 40 mph

 

[pcope]

I think my GPS app is suspect. The speedo doesnt work on the boat.

 

[Sea Rider]

When you say wanting more top end speed will it be while fully loaded or just cruising by yourself or with few passengers, Two complete different scenarios dialing a multipurpose single prop as weight affects RPM accordingly.

Happy Boating