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So I've bought the early access and I'm delighted at the ability to sign contracts. However something which confuses me is the jump in fuel consumption.
Most military contracts in the year 1900'ish asks for a pickup with a fuel consumption-level at 6 km/l. You should build such an engine while still having up towards 45 hp and being less than say 3500 cc and that isn't that difficult. But then you put the engine into a vehicle the fuel consumption jumps.
A engine which would go 6 km/l (I think the highest I got is 11 km/l) is suddenly down below the required 6 km/l.
Is this due to the fuel consumption being recalculated when you're building a vehicle? If so then it means that I have to focus more on light weight pickups, and fuel efficient engines/gearboxes.
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(02-16-2015, 06:31 PM)ChaapaNA Wrote: Most military contracts in the year 1900'ish asks for a pickup with a fuel consumption-level at 6 km/l. You should build such an engine while still having up towards 45 hp and being less than say 3500 cc and that isn't that difficult. But then you put the engine into a vehicle the fuel consumption jumps.
A engine which would go 6 km/l (I think the highest I got is 11 km/l) is suddenly down below the required 6 km/l.
Vehicle contracts require the vehicle's fuel consumption rating. Do not look at the engine's fuel rating because it is not the vehicle's fuel consumption, it's the engine's.
Quote:Is this due to the fuel consumption being recalculated when you're building a vehicle? If so then it means that I have to focus more on light weight pickups, and fuel efficient engines/gearboxes.
That is correct. Vehicles take into account, aerodynamic drag, rolling resistance and gearing. The fuel consumption listed for the engines is what is called Brake Specific Fuel Consumption. As in the amount of fuel it uses when it's not attached to anything.
To give you a real world example, Honda makes a 1.5L engine. Alone it uses about 300grams per kWh, estimated at around 45mpg. Inside a Honda Civic it does 40mpg. Now imagine putting it inside a Panzor Tank. If it's even able to move it, it'll be using a lot of fuel, probably 5-10mpg...
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good human beings save the world, so that bastards like me can keep creating art, become immortal.
if you read this after I am dead it means I made it." ― Charles Bukowski
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(02-17-2015, 08:23 PM)ChaapaNA Wrote: Ok superb. 
I finally managed to make a pickup which does 6km/l. However another question relating to this. Is the contract asking for the fuel consumption on the highway or in the city?
In 1.17 it's combined fuel mileage. So (City + Highway) / 2
In 1.17.5 and newer there is no longer city and highway, it's automatically combined.
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good human beings save the world, so that bastards like me can keep creating art, become immortal.
if you read this after I am dead it means I made it." ― Charles Bukowski
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What are the speeds that highway milage is calculated for? And if this is higher then top speed of the car, does this mean that the car will always do full throttle in that calculation. In that case a car that can't reach highway speeds has a very high fuel consumption and I have to focus more on increasing the top speed then on getting a low BSFC for the engine.
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(02-18-2015, 03:33 AM)Myquandro Wrote: What are the speeds that highway milage is calculated for? And if this is higher then top speed of the car, does this mean that the car will always do full throttle in that calculation. In that case a car that can't reach highway speeds has a very high fuel consumption and I have to focus more on increasing the top speed then on getting a low BSFC for the engine.
In 1.17, we take an optimal fuel mileage, then using gearing information adjust the higher end of the formula. Normally 10-30% higher than that "optimal" rating.
This system has been redesigned in 1.17.5, in 1.17.5 we calculate the rolling resistance of the vehicle at highway speeds 100km/h, figure out how much power you need to move it, and compare it to RPMs and factor in your gearing. We do similar things for acceleration, put the two numbers together and output a single combined mileage number instead of 2 numbers. In 1.17.5 if your vehicle does not reach those speeds, you'll be running at full throttle which will lower your numbers.
"great writers are indecent people, they live unfairly, saving the best part for paper.
good human beings save the world, so that bastards like me can keep creating art, become immortal.
if you read this after I am dead it means I made it." ― Charles Bukowski
