MH Hawker
Vice Admiral
- Joined
- Jul 13, 2011
- Messages
- 5,516
1988 Riviera Cruiser
length 20 feet
dry weight 1050 lbs
motor weight 130 lbs
beer n gear n gas 300 lbs
total 1480
1988 nissian NS40
40 HP two stroke
LU gear ratio 13:25
prop alu 3 blade 11 p 10.6 x 12.7
netural rpm= 1000
idle rpm= 850
WOT rpm= 5200-5800
test results
using a clamp on inductive tach + or -1 %
boat WOT=4275
boat speed GPS= 14 mpg
going by the 300 to 400 rule changing to
a 9 p would put it in the 4600 range
a 7 p would put it in the 5000 range
a 5 p would put it in the 5300 range
I would like to get it closer to the 5200 or 5400 opperating range and being as i often have it loaded down with 4 adults and 3 or 4 kids, and being as its a pontoon it needs all the help it can get on holeshot, I was thinking on going to a 4 blade alu prop but thier dosnt seam to be any in a 4 blade in the 7 p or 8 p range, so I it looks like i will have to use a 7 p in a 3 blade . that is of course if i am looking at it correctly any help would sure be appricated
length 20 feet
dry weight 1050 lbs
motor weight 130 lbs
beer n gear n gas 300 lbs
total 1480
1988 nissian NS40
40 HP two stroke
LU gear ratio 13:25
prop alu 3 blade 11 p 10.6 x 12.7
netural rpm= 1000
idle rpm= 850
WOT rpm= 5200-5800
test results
using a clamp on inductive tach + or -1 %
boat WOT=4275
boat speed GPS= 14 mpg
going by the 300 to 400 rule changing to
a 9 p would put it in the 4600 range
a 7 p would put it in the 5000 range
a 5 p would put it in the 5300 range
I would like to get it closer to the 5200 or 5400 opperating range and being as i often have it loaded down with 4 adults and 3 or 4 kids, and being as its a pontoon it needs all the help it can get on holeshot, I was thinking on going to a 4 blade alu prop but thier dosnt seam to be any in a 4 blade in the 7 p or 8 p range, so I it looks like i will have to use a 7 p in a 3 blade . that is of course if i am looking at it correctly any help would sure be appricated