Prop

[mgd7922]

Hey,
I've got a 2001 Nitro NX750 (17.5 foot) with a 2005 115 optimax engine.
When I bought the boat several years ago it had an offbrand prop with a 22 pitch. The boat had good speed, but had a lot of problems coming out the hole. Last year I went to the prop selector on the mercury website and got a 4 blade prop with a 19 pitch.
Now it comes out of the hole good, but it has so much torque that when I turn left I feel like I'm about to flip the boat so turning left I always turn real wide.

I'm assuming I need a prop between the two. With my new prop there wasn't a big speed drop, top speed may be 5 mph slower but I don't really go top speed that much. I'm more concerned with getting on plane then top speed, but I still want to be able to handle. Should I change the pitch, should I go back to 3 blade, or do both?

I also wondered with the change of the prop do I need to change the height of the motor on the boat?

Thanks

[bassfisher444]

You most likely need to raise the motor with the 4 blade prop, keep an eye on water pressure as well.

[JOE54]

different brands of props can have their own set off problems as suggested you may need to raise mtr and or change brands or get correct 3 blade , what was max rpm with 3 blade original prop loaded ????

[EuropeanAM]

One other note: Most boats that plane and achieve speeds in excess of 40 MPH are going to require SOME action when turning OTHER THAN just turning the wheel at higher speeds.

The higher the speed, the more critical these actions are (reducing RPM's, reducing trim angle, etc). That little NX will move right along with a 3 cylinder Opti... so make sure you're not hauling the mail at full trim and trying to make turns to port at 90-100% throttle settings.