Prop question

[magnum350]

I have a 21 ft. cuddy cabin with a 350 5.7L mercruiser with a 15.5 inch. 17 degree pitch prop. Would a 14.5 inch 19 degree pitch prop get me out the the hole quicker????

 

[steelespike]

Re: Prop question

You do need to read the stickys at the top of the prop forum and the helps on the prop store page.
Pitch is measured in inches, Increasing pitch (higher numbers) is like shifting a car into a higher gear
it may go faster but with less power.
Diameter is a secondary consideration and usually goes down as pitch goes up.
If you get us the info needed in the stickys we can help you decide what if any prop s change you may need.

 

[jestor68]

Re: Prop question

I have a 21 ft. cuddy cabin with a 350 5.7L mercruiser with a 15.5 inch. 17 degree pitch prop. Would a 14.5 inch 19 degree pitch prop get me out the the hole quicker????

I doubt it. What's the elevation where you boat?

 

[magnum350]

Re: Prop question

4800 ft above sea level

 

[jestor68]

Re: Prop question

HP loss= elevation X .03 X HP at sea level/1000.

For example, if your motor produced 300 HP at sea level, it would lose about 43.2 HP at 4800 foot elevation.

Assuming your motor may not be "fresh", the elevation factor may well be a big factor as to why you're not experiencing the good acceleration(power) that you should be getting with a 15.5 X 17 pitch prop.

We need to know what full throttle rpm your motor is attaining now in order to offer any suggestion. This assumes that your motor is in proper tune(running the best it can) given it's age/hours.

 

[magnum350]

Re: Prop question

Running very well I will try a 15 pitch and a 19 pitch till my 17 pitch is repaired. now I know what to look for in rpm range thanks to everyone.

 

[jestor68]

Re: Prop question

You wouldn't go up in pitch to improve your hole shot.

How bad is your 17 dinged up? Just a slight amount of damage can effect performance more than you might think.

There can also be a noticeable difference in performance between the various brands of props.

 

[magnum350]

Re: Prop question

Its very bad. Even a few chunks outta of it

 

[Mi duckdown]

Re: Prop question

Its very bad. Even a few chunks outta of it.
Should have mentioned That in the original post.
Why not rebuild that prop and see what happens.