Fuel economy blues / problems and weirdness

[CMDRSweeper]

I dunno if I am missing a value here or if the system is broken, but now that we have economy to play with, I decided to see if I could get some interesting fuel consumption values out of my burner engines.
The burner class of engine is essentially an engine that is designed to have the efficiency as low as possible, and it should be a disaster on the fuel consumption gauge.
So on my second test build after getting strange numbers I had these two engines:

Burner: 1998cc 8V OHV Carb engine
HP: 9.9 Hp
Efficiency: 0.38% or 20329 g/kWh

Eco: 1998cc 8V OHV DFI engine
HP: 144 Hp
Efficiency: 34.07% or 225.8 g/kWh

Now for the test I used almost identical parameters for the car except gearing as the estimated top speed varied between the engines.
However, in the Eco config, the car had a consumption of 3.84 liters per 100 km which is actually quite good.

But the burner engine is what gives me these strange results, it gives me a consumption of 0.59 liters per 100 km, which I just can't make any sense of.
Is there are a bug when you go extreme or am I missing something?

[Killrob]

Ohh, that is definitely not correct. My calculations say the fuel consumption should be around 170L/100km for the bad engine. We'll have a look at what such an extreme case does to the implementation of these calcs.
Cheers!

[nissanman]

is the bad engine knocking?

[Reaper392]

I can add to the fuel economy bug. I have a low revving engine that is too rich to run (which I use to get around the ~350mph gearbox crash). I just tested this in a car and got 427.9mpg (UK) (0.66L/100km)

[CMDRSweeper]

is the bad engine knocking?

The burner has such a low octane number it could run on 70 no problem
It does however have its mixture as rich as possible, the next step will actually prevent the engine from running.
To further sabotage its economy it is turbocharged with a boost of 0.0 Psi with an intercooler, its exhaust is designed for MAXIMUM restriction with a poor cat that I doubt would last very long.
Sadly we aren't allowed to combine a cat with leaded fuel, the destruction of the cat in such a combo would warm my heart (Yes I hate them)

[05u16hep]

I too find the fuel economy calculations a bit inaccurate, are they calculated by simulating an NEDC? I find mid size I6 and V8 engines do show up quite well but small naturally aspirated I4's seem to show better fuel economy than would be realistic.