Fuel consumption

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All modern engines need the same amount of fuel to deliver the same amount of power at wide open throttle. As long as the cars have the same amount of power and mass, the fuel consumption would be about the same.
This is simulated well in GT4.

Gasolin engines need a perfect fuel ratio at 100% load for not to blow or overheat. Concerning normal day to day driving the car manufactures use different tecniques/patents to shave off fuel in the low throttle range (0-50% engene load).

To simulate this accurately for each car in the game, I think would be wery time consuming for the developer. And it would not be relevant for a racing sim.
 
I've only got a 2 litre and it does 8mpg under acceleration. I think any mpg in the game will be estimates. Its not something I care about though tbh.
 
GTAnders
All modern engines need the same amount of fuel to deliver the same amount of power at wide open throttle.
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Sorry to nitpick, but this is absolutely not true. You are essentially saying that every modern engine has the same thermal efficiency. In reality, modern engines range from about 25% thermal efficiency for common gas engines to over 50% for the most efficient large (really, really large) stationary diesel engines.
 
gman07
Sorry to nitpick, but this is absolutely not true. You are essentially saying that every modern engine has the same thermal efficiency. In reality, modern engines range from about 25% thermal efficiency for common gas engines to over 50% for the most efficient large (really, really large) stationary diesel engines.
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Yes, thats right. Diesel engines are more thermal effective than gas engines. I think the most effective engine made is a giant japanese diesel engine used in an oil tanker. (52% thermal efficiency)

But I am talking about modern gas engines using the same spec fuel. At WOT they all need the ecsact same air fuel ratio.
 
GTAnders
Yes, thats right. Diesel engines are more thermal effective than gas engines. I think the most effective engine made is a giant japanese diesel engine used in an oil tanker. (52% thermal efficiency)

But I am talking about modern gas engines using the same spec fuel. At WOT they all need the ecsact same air fuel ratio.
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They need the same A/F ratio, which means that they need the same mass of air per unit of fuel burned. That doesn't necessarily mean they'll make the same power output from that amount of fuel and air though. Thus, they can make the same power with less fuel (and air, because A/F ratio is fixed) if they're more efficient.

I understand what you're saying, but it's not quite technically correct. Again, it's probably nitpicking but as an engineering student, I like to get technical. :)
 
At your level its probably not 100% correct. But I think you got my point:)

Unnecessary to simulate the axact fuel consumption for every car.

Any thoughts about how detailed the engine management is simulated?
A NA engine is easy to simulate, but I dont think turbo engines are correctly simulated in previous GT games.
 
People_Know_Me
I don't care so much as to what they do in terms of amount of fuel consumption.

I just hope that in the physics engine, they account for fuel spent in the weight and center of gravity of the car. Take a NASCAR for example. With a full tank of gas, the car is at a heavier weight, with more weight towards the rear end, and the center of gravity pushed back. It can make the car quite a bit squirly in some instances because of that. But, as you burn off fuel, that center of gravity moves forward, and the car becomes lighter, making it faster. With a fuller tank though, you get more weight over the rear axel making the rear tires grip better.

It's all so dynamic, and PD has claimed that this new physics engine is going to be as real as it gets (or so they implied), so I hope this isn't something overlooked.
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In your garden variety GT2 car, you have adjustable anti-roll bars to compensate for this. Look at some interior pics of Grand-Am cars and you'll see what I mean.

While I see where you're coming from; asking gamers to make in-game adjustments like that is a bit extreme. Better to just keep the balance of the car the same while decreasing weight as fuel burns off. Either way, it won't ruin the game nor do I think it would make it much better.
 
The fuel level is a big impact on the cars balance in most motorsports. In F1 and Champ cars the driver have to adjust the F/R brake balance during the race to optimize braking distances because of the COG moving forward as the fuel burns out.

In GT5P you have the option to adjust brakes, TCS, ASM, etc while driving.
This option is probably ment for endurance races.
 
I've been lurking on these forums a bit, but had to throw my .02 in:
Calculating consumption, at least close to real life, is really simple and I'm sure the people at PD did it.

All you need to do is establish efficiency for a motor (not hard to do honestly, at least in rough estimates, like a factor for size/configuration), power (which we know they can model in real time, the game knows how much power is demanded from the engine and sent to the rear wheels at all times), and time.

Power is directly tied to efficiency and power demanded (regardless of engine size or power potential, or even type of fuel), and when you factor in time you have consumption. They would basically know how much fuel is being used in real time, and just subtract that from fuel in the tank. Fuel also has a well defined weight (6.3 lbs/gal for gasoline) so it shouldn't be hard at all to model weight changes.

PD has had years to work on this, and there is a decent chance someone there already worked out a usable formula allowing them to just tie in the current power production of any car and an efficiency rating based on the engine to produce realistic fuel consumption.
 
SgtWhitten
I hope the fueling is part of the set up so we can adjust fuel levels for qualifying and then race etc. It would be great to set up your own pit strategies.
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That would be a great option to have. Though it can also hurt you if you get it wrong. But in all it would be great to have in the game.
 
fuel consumption huh? hmm idk my car is a 275hp all motor civic. i can only get 100 miles out of a full tank. 106 octane in 12 gallon tank btw. racing it on a track. so i want to see how it translate in the game.... but idk... maybe well be able to have an extra fuel cell in trunk for added mpg
 
I hope FC is realisitc for the specific cars, take selecting cars for an endurance race, you want to choose between a Nissan GTR and a Ferrari 458, do you take the 458 and know that you'll be faster than most other cars on the track but then have to spend more time in the pits refuelling, or do you take the GTR and hope that because you don't have to refuel as often, you can overtake the competitors as they stop?
 
That a got point on the cars; but we all know once we get some what through the game will start testing and such so we know what to expect. As with the competition that PD or our self’s will do may just throw all of us a loop. Only time will tell...
 
Wide open throttle, a Nissan Altima with a 2.5 L 4 cyl will do around 25L/100km according to the computer. So those numbers for a Tuned Corvetter are totally realistic IMO.
 
DestinyDanny
I hope FC is realisitc for the specific cars, take selecting cars for an endurance race, you want to choose between a Nissan GTR and a Ferrari 458, do you take the 458 and know that you'll be faster than most other cars on the track but then have to spend more time in the pits refuelling, or do you take the GTR and hope that because you don't have to refuel as often, you can overtake the competitors as they stop?
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👍
 
R34EVO9
fuel consumption huh? hmm idk my car is a 275hp all motor civic. i can only get 100 miles out of a full tank. 106 octane in 12 gallon tank btw. racing it on a track. so i want to see how it translate in the game.... but idk... maybe well be able to have an extra fuel cell in trunk for added mpg
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I would rather see a race fuel cell be put in if any mods done done the the car; mainly replacing body parts with CF and adding a cage. The extra mass of the extra tank on the car would slow it done.
 
As far as fuel consumption goes, I just hope they bring back the Prius at Tsukuba license test from GT4 Prologue, that was one of my favorite tests. You had to do a lap under a certain time while leaving a certain amount of gas in the tank 👍 Oh, and hopefully when you do run out of gas the car will stop instead of going, what 35mph?

Jerome
 
xNEVER-ONEx
I hope the in game fuel is cheaper than it is in real life.
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I'll second that :)
We had in GT4 and it was okay and made sense. In GT5 it'd probably be a lot more refined (the gas system not the gas), and be fine. I'm not worrying about that at all, PD would handle it well.
 
DestinyDanny
I hope FC is realisitc for the specific cars, take selecting cars for an endurance race, you want to choose between a Nissan GTR and a Ferrari 458, do you take the 458 and know that you'll be faster than most other cars on the track but then have to spend more time in the pits refuelling, or do you take the GTR and hope that because you don't have to refuel as often, you can overtake the competitors as they stop?
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I would think the 458 would get better mileage b/c it's lighter.

To accelerate an object to a given speed requires a certain amount of energy. If you have a 3400lb Toyota Prius and a 3400lbs Porsche 911 - both need the same amount of energy to accelerate to 60mph in say 10s. That's brisk street driving.

Those cars in that situation will use damn near the same amount of fuel. Any differences would come down to small efficiency differences.

A Nissan GTR does not get whatever the MPG rating is while having an output of nearly 500HP. And at speed; things like aerodynamic drag have a greater effect on fuel economy. Go for a long drive with your windows up then your windows down. You'll see what I'm on about.

There's too many variables to predict fuel consumption. High budget race teams even have to guess at times.
 
raytard
I've been lurking on these forums a bit, but had to throw my .02 in:
Calculating consumption, at least close to real life, is really simple and I'm sure the people at PD did it.

All you need to do is establish efficiency for a motor (not hard to do honestly, at least in rough estimates, like a factor for size/configuration), power (which we know they can model in real time, the game knows how much power is demanded from the engine and sent to the rear wheels at all times), and time.

Power is directly tied to efficiency and power demanded (regardless of engine size or power potential, or even type of fuel), and when you factor in time you have consumption. They would basically know how much fuel is being used in real time, and just subtract that from fuel in the tank. Fuel also has a well defined weight (6.3 lbs/gal for gasoline) so it shouldn't be hard at all to model weight changes.
PD has had years to work on this, and there is a decent chance someone there already worked out a usable formula allowing them to just tie in the current power production of any car and an efficiency rating based on the engine to produce realistic fuel consumption.
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Haha your name got me good.
Also I agree with the actual post. it shouldn't benhard to do and with all this time.
 
Well obviously the gasoline tanks are immensely huge.

The Veyron for example can last about 18 minutes when racing it at full (yeah, Top Gear said it. It's even in the manual!). So the whole tank should be empty in about 20-25 minutes max when racing it. The same with the new Mercedes SLS, the fuel and tires should be long gone after 20-25 minutes TOPS. I've managed to stay 3 times as long on the nurburgring with both cars, racing it to the maximum. Both fuel and tires were obviously wayyyy better then they are in real life.

I think it would be awesome if the fuel went down as quickly as in real life, it would force you to make pit stops way more often. It's just the price you pay when driving an extremely heavy and immensely powerful 16.4 liter V16!
 
From what I've seen, unfortunately it looks like all cars have a standard 120 liters racing fuel tank :(
Same problem as in GT4 (except there all fuel tanks had a 80 liters capacity)...
 
But you're not constantly flat out at 260mph at the nurburgring and I think thats the point Top Gear was making so it's probably pretty real fuel usage.
 
That's not how it works. Remember drag force squares with velocity and drag power is the cube of velocity. It's an exponential so if the car uses its fuel in 18 minutes @ 253mph it doesn't mean it'll use it in anywhere close to that at lower speeds.
 
its true.

diesel R10 ftw!! 35mpg*


*BS i just made that up. but your right, if u want a 16litre turbo, then downside of this is that it drinks petrol much faster than i can pour water down the plughole?
 
The Veyron can empty it's tank at top speed in about 12 mins, you can't get anywhere near that on the Nurburgring. I was pretty sure that Kaz said that cars use fuel at different rates and redlining is going have an adverse affect on your fuel consumption. Whether that is factored into the said vehicles' actual engine size and fuel management remains to be seen, but I would love to see that. This would make endurance races much more life like and force many to make decisions on different aspects of cars. Weight, power, engine size and diesel or gasoline.
 

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