21XDC Michael

[lpugh]

2003 cougar
hull weight 1500 lbs
250 Pro XS TK II gear case
ideal RPM 6000 limiter 6200
25 Fury 3 blade reworked
5900 rpm 76 MPH tournement loaded under almost all conditions
P to P is 2.75 currently (no help when raising the motor further)
To date this is the best overall prop, 26 I have is faster
25 Fury 4 is good under 70 but very poor above 72 or more
Tempest not even close
Boat gest a lot of air under it and runs the at very at low trim up, lift is not a problem unless there is actually to much
This boat will top 80 under very good conditions and when I can keep it settled down

Problem is very hard to control chine walk above 75 , doable but a wind gust or boat wake sets it off faster than I can compensate, I think there should be a way to improve this
I would ask you what props would recommend to try first, A prop that I could drive better at 76 mph would probably be faster overall as I might not have to trim down as often or as much
Bravo XS and pro max are peaking my interest ? I have no personnel experience with this two props
Also what pitch to replace the 25 Fury, leaning towards one to achieve 6000 to 6100 and tighten it up if needed

[21XDC]

The TXP3 is fast, But hard to get. The TXP-OT4 is a nice 4 blade is also hard to get.... The ProMax would be one to consider and easier to get. I have a 28P that does well, But holeshot surges. I had Mark add dual PVS holes and I can easily get on plane at 1/4 throttle. You probably need the 26P

[lpugh]

Thanks Mike

[lpugh]

21XDC Michael
I have a labbed 26 promax on the way, What's your opinion on as starting place for for pvs plugs. I am thinking it will require at least partial PVS restrictions as it is an over the hub exhaust
2003 cougar (1450 hull weight) 250pxs, TK II gear case, will start at the present height of 2.75 in. TK II cases do cause more blow out at nose over.
Currently a reworked 25 Fury with no plugs and perfect rpm flare, Hope this prop improves the high speed handling. I am thinking 2 solids to start with. I have a hard time believing that with all open it would get on the pad with this gearcase

[21XDC]

I agree. That gearcase may be a problem in the venting/surging department. I'd be guessing on venting. Let us know how it does.

[lpugh]

In thinking about this props design I believe that better performance may be obtained with out using a cavitation ring if I can get the hole shot right with pvs, your opinion on this. I would think it might a little faster without the ring as this boat has a lot of lift. Over the hub may reduce prop resistance in the water freeing it up little

[21XDC]

I hate using a cav ring. I try not to recommend them. But some cases are needed if one chooses to use the prop. I wish they made the ProMax in a large tube like the Fury4.

I doubt you will get the holeshot right by plugging PVS holes. Good Luck

[lpugh]

Tried the prop out this AM.
No cave ring and 4 solid plugs
Hole shot does not flash up as quick, at nose over flares to 5000 rpm but holds there even at full throttle, slower hole shot time than the 25 fury
No steering torque and drives like power steering at 3 in p to p
about 1 mph slower than the fury
Solved my handling problem, a little walk 71 to 75 and then no walk at all
Now the boat does not demand 150 lbs extra weight on the starboard side, reversed drivers and handle the same, 150 lb vs 325 occupants
Forgot this earlier, even at max trim, the rooster tail is low, nose feels like it is pointed to the sky and no walk at 75 also very little speed drop at this level
So far 76 mph @ 6000 rpm, did not have much time for tuning this am had to get to work

Thanks for all the advice Leon Pugh