Knot Salted
Senior Member
- Joined
- Mar 16, 2015
- Messages
- 322
- Location
- USA
- Vessel Name
- Knot Salted
- Vessel Make
- 1981 Californian 34 LRC
Hi All,
KS (a 1981 Californian 34LRC) is powered by twin Perkins T6.354 engines rated at 200hp each.
Props on the boat, and the old spares are Michigan Wheel three blade 22x21.
I want to presume, and from TF discussions they appear to be factory original.
At 20,000lb or so, we seem to be over propped.
Reasoning that Engine raings are:
2400 RPM max
2250 max sustained cruise
Boat top speed is 18-20kts?
We can make 17 kts on a good day, and WOT will sometimes hit 2270, but usually more like 2170 on the mechanical tachs. I realize that there are better ways to measure RPM.
ACME propeller says We are over propped and need four blade 20X18 lightly cupped props to allow more RPM based on our boat weight, dimensions and HP.
I surely do not want to under-prop.
Any opinions or thoughts please.
KS (a 1981 Californian 34LRC) is powered by twin Perkins T6.354 engines rated at 200hp each.
Props on the boat, and the old spares are Michigan Wheel three blade 22x21.
I want to presume, and from TF discussions they appear to be factory original.
At 20,000lb or so, we seem to be over propped.
Reasoning that Engine raings are:
2400 RPM max
2250 max sustained cruise
Boat top speed is 18-20kts?
We can make 17 kts on a good day, and WOT will sometimes hit 2270, but usually more like 2170 on the mechanical tachs. I realize that there are better ways to measure RPM.
ACME propeller says We are over propped and need four blade 20X18 lightly cupped props to allow more RPM based on our boat weight, dimensions and HP.
I surely do not want to under-prop.
Any opinions or thoughts please.