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[TURBO (@)....]

Ok this is a strang thing so i accidently left my playstation on while in photomode and i was racing untill i had to go.So when i come back i relized that i had left my playstation on so i turn the tv on to see that my R8 had bin sitting on the side of the trac for an hour and a half .Then i look at my gas meter and i still had a full tank off gas hmm?.In real life dosnt a car consume more gas at an idle?

 

[DJ-CiviC]

this aint life... this is a video game...

 

[Wolfe]

Not all modes of the game feature fuel consumption.

 

[Kent]

Actually, no, cars consume less fuel at idle.

Just think of it in terms of RPMs.

Regardless of any other factors, just think of the RPMs.

Each RPM is one "action."
Each action uses "X" amount of gas...

At 1000 RPMs you get 1000X.
At 2000 RPMs you get 2000X.

Basically, with more RPMs you are doing the same action more times in the same amount of time.

Simply put, idle uses the least amount of gas possible and for every little bit of increase in your RPMs you are using more gas.

 

[Wolfe]

Hmm, I missed the "idle = more fuel consumption" part.

 

[DJ-CiviC]

Actually, no, cars consume less fuel at idle.

Just think of it in terms of RPMs.

Regardless of any other factors, just think of the RPMs.

Each RPM is one "action."
Each action uses "X" amount of gas...

At 1000 RPMs you get 1000X.
At 2000 RPMs you get 2000X.

Basically, with more RPMs you are doing the same action more times in the same amount of time.

Simply put, idle uses the least amount of gas possible and for every little bit of increase in your RPMs you are using more gas.

You're not totally true. Somebody told me that the engine consumes more gas at low rpm than at high rpm* (I dont mean when floored). I could be wrong...

 

[the Interceptor]

It works like this:

The engine consumes the most fuel when you're accelerating. The amount ist uses depends on the rate of acceleration, the speed you're already driving, the gear you're in and so on. When you let the car roll while still in gear, it uses no fuel, because a clever system stops the fuel pump, as the moving mass of the car makes the engine go.
When driving at a certain speed, the engine uses more fuel at high revs than at low revs. But when you're standings still, you only use little fuel. Still, your mpg are 0, cause you're still using fuel, but you're not moving at all.

I don't think that this has found its way into GT4 though.

Regards
the Interceptor

 

[Mad Murphy NZ]

Luckily GT4 doesn't include overheating... Leaving a race car to idle for that long would mean it would overheat.

 

[gibus]

Luckily GT4 doesn't include overheating... Leaving a race car to idle for that long would mean it would overheat.

I don't think so. How would it race the entire 24h le Mans race if keeping it idle for an hour and a half would over heat it.. I imagine that flooring the car for 1 minute would overheat it then.. I'm assuming they use liquid cooling and not air cooling. The worst thing you can do to a air cooled car is leave it still. My dad experienced this once in a traffic jam... not funny!

 

[Mad Murphy NZ]

Obviously you don't understand how cooling works. If there's no air coming onto the radiator then there's nothing to cool the water. I've seen plenty of cars in races overheat/get too hot sitting on starting grids idling for too long. Same thing can happen if cars are racing together in a group for extended periods of time, they can't get enough cool air and will often pull out of the slipstream to prevent overheating.

 

[G.T]

In real life dosnt a car consume more gas at an idle?

What made you think that?

Well, Kent explained it, the more RPM's, the more fuel your car uses. That isn't completely true though, say, you can find a certain RPM and speed on the motorway to get the most MPG as possible. 60mph in 5th was the best in my Dad's Mazda 6, I can't remember what the MPG was, but more fuel was used when you went slower and faster than 60 in 5th.

 

[gibus]

Obviously you don't understand how cooling works. If there's no air coming onto the radiator then there's nothing to cool the water. I've seen plenty of cars in races overheat/get too hot sitting on starting grids idling for too long. Same thing can happen if cars are racing together in a group for extended periods of time, they can't get enough cool air and will often pull out of the slipstream to prevent overheating.

Ok thanks for explaining

 

[Mad Matt]

Let's look at this logically:

Diesel and petrol engines work by burning a mixture of the fuel and air. So the calculation is to do with the amount of fuel in the mixture and the number of times that mixture is used (RPM).

So a car always uses some fuel, even when idling or coasting, in fact as long as the engine is on. Some modern cars with computers will tell you your current consumption as mpg or l/100km and when you get stuck in traffic they'll tell you how many hours you can sit still for before you run out of fuel.

For cooling: Most modern cars can idle indefinitely without overheating as the fan will come on to cool them down and they are designed for this. This doesn't apply to cars like those used for F1 as the cooling is only designed to work at speed.

I hope that clears it up.

 

[the Interceptor]

So a car always uses some fuel, even when idling or coasting, in fact as long as the engine is on.

That's not entirely true. Modern cars use a system that stops the fuel flow completely when the car is rolling in gear and you don't press the accelerator.

Regards
the Interceptor

 

[Verbal]

Actually, no, cars consume less fuel at idle.

Since you're using fuel without moving, your mileage won't be that great though.

 

[danny30001]

put its simply more rpm = more air = more fuel = more fule consumption

 

[Mad Matt]

Cars don't cut off the fuel when they idle, if they did the engine wouldn't turn over! A car idles at less than 1000 rpm, to do that idling it needs to use some petrol. Modern cars adjust the mixture to use the minimum possible, but they have to use some!

 

[phonypoly]

This is getting fuel-tile

Think of an idling engine, as a pot of boiling water..
If the burner's heat is low (low RPM's), the water will gently boil and less water will evaporate, but if the burner's heat is raised (more RPM's) more water will evaporate (more fuel consumption), except for when a car is on highway speeds, the electronics/computers, control the airflow delivered to the engine fuel mix, allowing more air and less fuel, thus; reason why a car will consume more fuel at city driving, stop/go/stop/go and less fuel at highway speeds, more constant.

There are cars with engines that cut off one or more cylinders at highway speed, or the fuel supply to the engine is reduced, allowing more air instead (see: air flow sensor)..
Did i just confuse you even more? i'm confused myself ..

 

[Dave_George]

All the answers here seem to apply to rpms, dont foget that fuel consumption is also affected by throttle position, you can be cruising at 5000rpm and only just have the throttle open which will use less fuel than accelerating at 5000rpm with the throttle fully open, same rpm, completely different fuel consumption.....

 

[Kent]

Ok, first off, this is not about Miles-per-Gallon.

This is about gross fuel consumption. 👍

That said, I stick to what I said before.

It's very simple, it really is.

Doing something one time uses X amount of energy, doing the same thing more times uses more energy.

Now since this isn't really about GT4 anymore I am moving this thread to the automotive section of the GTP (since that's where this belongs).

Once again though...
Low RPM = Low Fuel Consumption
High RPM = High Fuel Consumption

Btw, what G.T. said is also correct...
Certain speeds allow engines better MPG in certain gears... That's why the speed limits were mostly dropped to 55mph during the gas crisis of the 70's.


I live in Louisiana where the interstates are 70mph.
(I do 90mph and more on a regular basis )
('98 Toyota Camry 4cyl.)

 

[TURBO (@)....]

Ah now that i have read all of your post i have learned alot about a car and Fule consumtoin. Thank's for all the reply's

 

[Dave A]

You're not totally true. Somebody told me that the engine consumes more gas at low rpm than at high rpm* (I dont mean when floored). I could be wrong...

In general, it's as simple as the higher the rev's, the more work the engine is doing and the mire fuel it's buring as a result. More revs = more fuel burnt = Lower economy.

 

[Mad Matt]

Not quite right! It's to do with throttle position as well, so 1500rpm on a hill uses more fuel then 1500rpm on the flat , but I thought we'd been through this already in this thread?

 

[iceburns288]

Also remember when accelerating that you use more gas depending on your powerband. It's not always necessarily revs. If you're driving a Honda with very little torque and you try accelerating from 2000rpm in say, third or fourth gear, it's going to need a lot more throttle and a lot more gas (effort) to build up speed. If you were in 5 or 6000 rpm in third gear and wanted to accelerate, it would require a lot less throttle to do so because that's where the 'meat' of the power band is.

 

[dkstz]

All the answers here seem to apply to rpms, dont foget that fuel consumption is also affected by throttle position, you can be cruising at 5000rpm and only just have the throttle open which will use less fuel than accelerating at 5000rpm with the throttle fully open, same rpm, completely different fuel consumption.....

Hmm there's a website here that a few known "auto" journalists write on. They have tested with the same car (a Polo I think) in varios situations (highway, city traffic and mountain-like roads) when a car is consuming more and less fuel, according to the car's own computer.
Thay proved that consumption is strictly related to rpm, and the throttle wide open is no excuse to burn more fuel. The car consumed more driving at 3rd gear with medium revs and just a little bit of throttle than in 5th with full throttle and very low rpm (but not jerking of course).

And of course, the city was winner in making the car burn fuel, then the roads and the the highways.

bye

 

[RobcioPL]

Obviously you don't understand how cooling works. If there's no air coming onto the radiator then there's nothing to cool the water. I've seen plenty of cars in races overheat/get too hot sitting on starting grids idling for too long. Same thing can happen if cars are racing together in a group for extended periods of time, they can't get enough cool air and will often pull out of the slipstream to prevent overheating.

Ummm no.............

A race car could stay at idle for a long time and nothing would happen. Your telling me a car pushing 10K rpm for 24hours, wont overheat, but a car standing at idle, which gets air too, overheats.

 

[a6m5]

Don't laugh(too hard), but I've left a car running for few hours and locked it up at the same time. I had spent my lunch break in my '96 Protege, but when I left the car, I locked it with my key in the ignition with the car still running. Unfortunately, I didn't notice this until I was off work, like 5 hours later, I think. The car was OK, did not overheat and I didn't even notice the change in fuel level, so it sipped very little gas.

 

[retsmah]

A race car could stay at idle for a long time and nothing would happen. Your telling me a car pushing 10K rpm for 24hours, wont overheat, but a car standing at idle, which gets air too, overheats.

When the car is moving it's getting a lot of air flow through it's radiators. At idle it is either getting no airflow, or whatever air flow is provided by cooling fans. With big enough fans you could get the car to idle without overheating... usually they don't do that though, since the car shouldn't be sitting idling for extended periods of time, big powerful fans would be unneccesary weight, and would just get in the way of airflow to the radiator once the car is moving.

 

[RobcioPL]

When the car is moving it's getting a lot of air flow through it's radiators. At idle it is either getting no airflow, or whatever air flow is provided by cooling fans. With big enough fans you could get the car to idle without overheating... usually they don't do that though, since the car shouldn't be sitting idling for extended periods of time, big powerful fans would be unneccesary weight, and would just get in the way of airflow to the radiator once the car is moving.

So you think all this air flow and fans will keep an engine cooler at 10,000rpm? I dont think so. Then explain to me why brakes turn red when braking, but they dont while standing still. The breaks get air flow to them too.

 

[Duke]

So you think all this air flow and fans will keep an engine cooler at 10,000rpm? I dont think so. Then explain to me why brakes turn red when braking, but they dont while standing still. The breaks get air flow to them too.

Are you being dense on purpose, or do you really not understand this?

Brakes generate heat through friction when they are applied. That's how they stop the car - they transfer kinetic energy into thermal energy.

A radiator, on the other hand, does not generate more heat while in motion. In fact, it is a heat exchanger, which is designed to cool the liquid by radiating waste heat into the air via the coils and fins of the radiator housing.

The radiator, being a heat exchanger, is entirely dependent on airflow through it in order to carry the waste heat away from the coolant. Otherwise, it simply heats the air in the immediate vicinty more and more until it loses efficiency and the car overheats.

This is why cars have fans - to guarantee a continuous supply of fresh cool airflow through the heat exchanger.