Will33
Member
Is there a rule of thumb for power to weight ratio on a planning hull boat. Was speaking to someone today who said rule of thumb is 50hp to 1 tonne, anyone have any views/comments on this?
Thanks
Will
Thanks
Will
Planning Hull - Power Weight Ratio?
- Thread starter Will33
- Start date
zeros
New member
double if you want any sort of performance I would have thought.
D
Deleted User YDKXO
Guest
Yup, not way out but with peeps demanding 30+ knots these days, more like 75hp per tonne
JKay
New member
Hi Will With a single engine in a carrera I would think 165 hp minimum to plane lightly laden as you'll be about 2and a 1/2 ton. It might take a while to get up but will be economical for all your broads cruising and good for 24/25 knots and cruise at 20 knots
Proof of the pudding Early next season when my mate commisions his carrera with a new single kad 32 for £11000
cheers and good luck Joe /forums/images/graemlins/smile.gif
Proof of the pudding Early next season when my mate commisions his carrera with a new single kad 32 for £11000
cheers and good luck Joe /forums/images/graemlins/smile.gif
Its_Only_Money
New member
Will be different depending on whether you are talking diesel or petrol, the reason is the engine has to have enough mid-range torque to get the boat over its bow-wave and onto the plane, once there then Hp defines top speed, insufficient torque and she may not be able to plane at all without a seriously fine pitch prop.
I'd work around:
100Hp/ton if petrol (ie a 4.3 in a Carrera isn't big enough IMHO)
75Hp/ton if diesel
Top speed will be down on the diesel compared to the petrol (but maybe not by as much as the power difference implies), but they would give similar over-the-hump performance.
I'd work around:
100Hp/ton if petrol (ie a 4.3 in a Carrera isn't big enough IMHO)
75Hp/ton if diesel
Top speed will be down on the diesel compared to the petrol (but maybe not by as much as the power difference implies), but they would give similar over-the-hump performance.
brianrunyard
New member
I read somewhere:
50 hp per ton should plane
65 hp per ton will plane
50 hp per ton should plane
65 hp per ton will plane
David2452
Active member
[ QUOTE ]
Will be different depending on whether you are talking diesel or petrol,
[/ QUOTE ] Right on
Also which planing hull? this can be anything from a "tea tray" to a full deep V with an acute deadrise all the way to the transom and any combination of the two, obviously power required will increase from that needed by the "tea tray" progressively towards the much larger requirement of the full blown deep V, and then there are cats, cathedrals dories etc. It does seem to me that the softer the ride you want the more power you need to achieve it.
David.
Will be different depending on whether you are talking diesel or petrol,
[/ QUOTE ] Right on
Also which planing hull? this can be anything from a "tea tray" to a full deep V with an acute deadrise all the way to the transom and any combination of the two, obviously power required will increase from that needed by the "tea tray" progressively towards the much larger requirement of the full blown deep V, and then there are cats, cathedrals dories etc. It does seem to me that the softer the ride you want the more power you need to achieve it.
David.
