Jeff S
Newbie
- Joined
- Mar 14, 2014
- Messages
- 4
- Location
- USA
- Vessel Name
- Sea Psalms
- Vessel Make
- Davis International/42
Hello,
I have a 1977 Davis (Defever) 40' Trawler. (14"-7" beam, 4' draft)
Single Ford Lehman 120 - 2500 RPM max.
Velvet drive gearbox 2.37-1 ratio, 39,000 lbs+/_
Current prop 25x16 3 blade RH, 1.75" shaft
At slack current I run at 2200-2300 to maintain 8 knots.
I talked to another owner of an identical boat that is over propped with a 25x21 prop and he runs approx. 1600 RPM to get 8 knots, but cannot reach the 2500 RPM's.
So, I am looking to find the optimal pitch/prop type to get off the top end of my RPM's, maintain the 8 knots and help my fuel efficiency.
Any comments would be appreciated!
Jeff
I have a 1977 Davis (Defever) 40' Trawler. (14"-7" beam, 4' draft)
Single Ford Lehman 120 - 2500 RPM max.
Velvet drive gearbox 2.37-1 ratio, 39,000 lbs+/_
Current prop 25x16 3 blade RH, 1.75" shaft
At slack current I run at 2200-2300 to maintain 8 knots.
I talked to another owner of an identical boat that is over propped with a 25x21 prop and he runs approx. 1600 RPM to get 8 knots, but cannot reach the 2500 RPM's.
So, I am looking to find the optimal pitch/prop type to get off the top end of my RPM's, maintain the 8 knots and help my fuel efficiency.
Any comments would be appreciated!
Jeff