prop question

[Tony Archer]

Hi. Ihave a nitro 180f/s with a 175 evinrude. The prop im running now is an aluminum 14.25x23p. The boat runs 5550 wot at 53mph on gps. Thats with 20gals of gas,2batts. myself and the wife. Not much of a load. My question is im looking to changing props to get the rpm down to 5500 or under at wot without losing top speed or even gaining some. The two props im loooking at are a Renegade 13.25x25p 4 blade w/vent holes. The other is a Raker 14.25x24p 3 blade vented. Both are stainless steel. Anyone tell me how much of a difference either of these would make and which woul be the best one to get?? Thankyou.:unsure:

 

[David Munaretto]

You aren't going to drop 50 RPMs by going up a pitch, you're going to drop like 200-300 RPM. Why do you want to drop 50RPM? Sounds like you're propped out right as it is...go with a 23Pitch I'd think... and yes, go stainless.

 

[Derek Chance]

I am with David. you don't want to worry about 50 rpms. you prop up and it will be too much prop and you will be lagging your motor which is hard on them. However I would think that a 175 should have a better top end than 53mph. do you have a jackplate? how low is the motor height? What is your water pressure at wide open throttle?

 

[Tony Archer]

No jackplate. Motor height from the pad to cavitation plate is at 3". Motor can be moved up another inch. Water pressure is around 13psi at wot. I also was thinking the top end should be around 60 or so. Any ideas?? Thanks.



Went and remeasured the height. From pad to center of prop shaft is 5.25".

 

[joseph currier]

53mph for 180 f/s sounds pretty special to me your not running a z-7 you seem to have high expectations.

my boat is just at 63mph 5400 rpm and it is a baSS BOAT not a fish and ski wich should run slower because of the weight and design that is deeper.

 

[Bob Bourget2]

According to the rigging charts, the motor should be mounted 5/8" above the transom, and if using an S/S prop, the recommendation was a 24" RAKER. If the boat gained weight over the years, going DOWN to a 22" Raker would be in order. Mid-to-high 5500-5700 is NOT a problem with that engine......no higher though....

 

[Tony Archer]

Thanks for your personal opinon Joe. Yes my 180f/s is special to me. No its not a Z-7. And no i don't have high expectations. Just know it can run better. As far as a bass boat, i do catch plenty of bass out of it. Hmmm. Maybe yours can use a little tweeking. Have a good day.

 

[Tony Archer]

To Bob B. Thankyou very much for the imput. I will recheck the motor height and go with the Raker prop. Will let you know how it went once i get the prop on and reset the motor. Again thankyou!!!