the nodding donkey:
alamcculloch:
When I was doing the sailing instructor bit we had a ski boat that was fuelled by LPG . The lump was a 6 litre Chrysler ,to pull skiers up you nee a lot of power for fast acceleration. When it was out of service the boss hired in a petrol boat and it used so much fuel that it wasn’t economical to run it at all.A good example of how the intended use of the vessel, determines the engine, and so the fuel. Fast boats need a fast spinning propeller. Due to inertia laws, a fast spinning prop cant be very big, and a smaller prop needs to spin faster to displace the required amount of water. Hence fast revving petrol engines for speed boats and larger cruisers that need to be got on the plane (keep googling Carryfast). So fast boats, favour petrol engines, or LPG to keep the cost down. Slow boats, can do with an economical diesel engine, because their props can be bigger, and therefore don’t need to spin fast.
So you’ve never heard of a gearbox being needed between prop shaft and engine.IE you don’t connect a boat engine directly to the prop.Hence you can have fast diesel or petrol boats it makes no bleedin difference.
powerandmotoryacht.com/maint … ansmission
You do know that with a 6 litre Chrysler,let alone 2,he’s obviously talking about an inboard motor in which case surely it would have blown itself out of water before doing anything useful going by your bs.
As for petrol/diesel engines v planing hulls.Oh wait just like fast diesel or petrol boats I’m sure that petrol MTB’s were semi displacement deep V hulls like their diesel engined German E Boat counterparts and just like numerous types of diesel and petrol motor yachts since.How do you explain that.
Suggest you’re the one that needs the help of google not me.