Formula 34 PC Kad42 twin Diesels

[BruceK]

That was on brokerage for £36k and still is at the moment unless the broker is slow. The 36 on shafts as to mine a 34 on legs is distinguishable by one main factor.

FUEL CONSUMPTION.

She's a lovely boat but goddamn thirsty and I turned an example in Pwllheli down. Other than that there is very little in the interior layout but with a bigger and more comfortable lower cockpit on the 36. That 2 foot makes a difference for sure.

[Ianfs]

Here too..........................

http://www.boatsandoutboards.co.uk/Cruiser/formula-36pc/115981#Xc5Zs2r4zpICUjoA.97

We have considered it but not sure what Mercruiser diesels are like long term. Typically I've heard good and bad about them, but fuel consumption must be high.

I still say it Bruce, that's a cracking boat you have there.

[shibbs]

So why is there a difference in fuel consumption between shafts and legs? I'd never have thought there'd be a difference?

[BruceK]

Ah no. Significant difference in fuel consumption between shafts and legs. A lot has to do with shaft angle and prop size. Also those are 7.4 litre v8 diesels... two of. My KADS are 3.7 litre each but make only 60hp less. Shaft drives spin big props slower but need loads of torque to do so because the bigger endines dont rev to high so gearbox reduction becomes limited hence the bigger engines. Doesn't make them any faster or more efficient when talking planing speeds though. Legs are limited to size of boat because there is only so much torque you can push through them. 40 foot/15 tonnes being about the largest. The 36 really sits in leg territory.
Legs however are vulnerable, expensive to maintain or repair etc so you see a lot of bias and preferences between the two.