I've had petrol conversions since the late 80's in Australia. We used diesel conversions in mining industry when doing my trade
. Busses are commonly converted to diesel/gas for public transport in New Zealand
Certainly with petrol conversions I've never seen a HP increase but always about a 5% loss in power. But the main benefit is in cheaper fuel. An added advantage is cleaner emissions and cleaner engine, less maintenance
I've never known of a power increase with diesel conversions either. It's usually done for no other reason than for fuel economy.
Another issue is cost of installation
. For the past 25 years there was a great inventive to convert. Our federal government
paid half the conversion cost with the remainder soon made up on fuel savings. But that no loner apples and the government
is taxing LP with it increasing each year. Quite frankly it won't be worth economically doing a conversion at all. Busses convert for no other reason than fuel economy and they claim environmental conscienceness.
On a boat? I can't see any benefit at all.
Very expensive to convert diesel with duel fuel. It's more than half the cost of a new engine.
Very difficult to fill. It's illegal to fill up from a fuel bowser, at least in Australia.
Dangerous. The lpg we use for cooking/heating is risky enough as it is.
It's impractical for reasons stated. Theres a hell of a lot of weight in a full 80 ltr tank
determines your max speed not HP, so what would be the gain.
Anyway that's my take on it.