I put a stock Maximus on my Daytona and it gets on plane without too much difficulty but it is causing transom lift to the point that I have to either learn how much trim to use to get the bow up or learn how to drive a three point hydro. I have the bell cut off the back of the prop.
I am going to see if I can get on plane with the stock Bravo 28 ( bell cut off ) and the labbed Bravo 30 you made for me.
The question I have is with my boat fully surfacing the prop. ( prop shaft is 2 inches above the low point on the hull with an IMCO neutral extension box ) Can You add diameter or blade area to the Bravo props to aid in planing and to lower slip. Or will this just cause transom lift.
If I can get on plane I feel that the Bravo 4 blade will be the best prop for the boat.
The boat really loves the Maximus for everthing except top speed. It really stays hooked up at low planing speeds and cruise.
OR should I just have you lab the 5 blade. I can't lose ANY blade area.
Thanks
Steve

More blade area = more stern lift

Increased cupping and rake should add bite and bow lift

What about spacing the drive down an inch??? and trying a Bravo prop???

I installed the drive at the height that Eliminator told me would be the best height for top speed. I have a -2 IMCO shortie lower also so if I need to go down an inch I can just swap lowers. BUT that is not the route I want to go. I need to find the best prop for the boat. I am more interested in top speed than best cruise IF I can get on plane with that prop.

Were you by any chance out on gun lake with this boat last week?

Labbing the Maximus usually involves reducing diameter to decrease stern lift and increase rpm. (as well as other adjustments)
Because it is 5 blades we can lose some blade area since it should still stay hooked up.

We don't want to add blades area to the B1 prop. A spacer is a option. If done just right, you shouldn't lose speed.
You hull type is very specific with X dimension. They don't like the X as high as people believe they should be.

Brett

WELL - I got it out Sunday for 1 1/2 hours at Hardy pond with the stock Bravo 28 pitch prop installed ( the bell is cut off the back ) With 5/8 tanks of fuel the boat gets on plane - it isn't pretty ( about 7 to 10 seconds at 6000 RPM ) I will tell you the boat really liked the prop once up on plane. I didn't get a chance to try the labbed 30 Bravo you built for me because the seawater impellar went bad and my engine temp jumped way up.
I am going to have to modify the water pick up on the front of the IMCO -3 lower so that it is more in contact with the water.
I still have to trim from 5 ( neutral setting ) to 7 or 8 to get top speed and at top speed if I try to trim back in I lose speed.
But once on plane if I roll into the throttle at 40 MPH the boat accelerates like someone stepped on it's tail.
I got up to 6100 RPM - need 300 more.
I won't tell you what the top speed because I want to here what the cat experts here think m top speed would be with 800 HP. ( other thread )
Needless to say I think the drive height is perfect.

Brett - I think I am going to send you my Maximus and let you work your magic. I will use that prop when I have a full load.
Steve.

Ok,

Let me know when it is on its way so I can look for it.


Brett

The lack of a diffuser ring is most likely hurting the ability to get on plane.

Cutting off the diffuser ring did cause it to be more difficult but I blocked the airflow through the drive by installing a piece of LEXAN at the top of the exhaust passageway where the upper and lower halves split.
This blocks all airflow through the drive and one advantage is it also traps water in the upper half every time the boat goes off plane. This trapped water helps cool the drive at high speed by boiling off from the INSIDE of the drive.
This modification made getting on plane with the ring removed almost the same as with it on.