Decreasing prop slip on 31/32
09-18-2016, 09:09 PM
#1
Registered
Thread Starter
Decreasing prop slip on 31/32
I have a 93' 31 thunder
5400 rpm
1.5 gear
24 pitch Bravo's
67.5 GPS
@17% slip.
Tried multiple trim positions kinda found the sweet spot I think. To reduce slip are my only options to step up to 5 blades?.
Any advice is appreciated
5400 rpm
1.5 gear
24 pitch Bravo's
67.5 GPS
@17% slip.
Tried multiple trim positions kinda found the sweet spot I think. To reduce slip are my only options to step up to 5 blades?.
Any advice is appreciated
09-19-2016, 04:54 PM
#5
Registered
Thread Starter
I thought 17% was hideous. I just assumed @ 12% would be more like it. I am not to concerned about top speed, would like to get slip down and if I were to use 5 blades I would think my cruise mph would go up some what, most of the time the boat is ran 3000-4000 rpm. But I am up for any thoughts from fellow members
09-20-2016, 01:47 AM
#6
Charter Member # 55
Charter Member
Actually you are closer 15% slip. Bravo props are stamped heavy on pitch and are really .5-1" less than stamped. Use 23.2 for your pitch.
15% slip is pretty decent and about average for most 32's I've read about.
I'm at about 12-13% from cruise through WOT. I would attribute my lower slip numbers to having extension boxes and my props being BBlades labbed for the boat.
15% slip is pretty decent and about average for most 32's I've read about.
I'm at about 12-13% from cruise through WOT. I would attribute my lower slip numbers to having extension boxes and my props being BBlades labbed for the boat.
Last edited by Griff; 09-20-2016 at 01:51 AM.
09-20-2016, 06:31 AM
#7
Registered
09-20-2016, 08:11 AM
#8
Registered
Thread Starter
This was the boat designed for outboards. I think the first owner changed his mind and went bravo/big blocks. I beleive he rigged it so I don't know if it is setup like factory. Tonight I will see my propshaft to bottom relationship so we have a idea.
09-20-2016, 08:15 AM
#9
Registered
Thread Starter
Actually you are closer 15% slip. Bravo props are stamped heavy on pitch and are really .5-1" less than stamped. Use 23.2 for your pitch.
15% slip is pretty decent and about average for most 32's I've read about.
I'm at about 12-13% from cruise through WOT. I would attribute my lower slip numbers to having extension boxes and my props being BBlades labbed for the boat.
15% slip is pretty decent and about average for most 32's I've read about.
I'm at about 12-13% from cruise through WOT. I would attribute my lower slip numbers to having extension boxes and my props being BBlades labbed for the boat.
