PDA

View Full Version : [REPORTED] Fuel mapping useless for saving fuel



Asturbo
24-02-2018, 21:30
I was in a race with not enough fuel to finish, and I changed the engine map to lean, trying to avoid a pit stop. Inmediatly, the lap times increased about 2", but surprisingly the fuel consumption didn’t change, evenmore it looks that the car was wasting more fuel beeing slower.

After that, I did some test to confirm the issue. I select Indianapolis with the Ferrari GT3 and 8 laps (full gas all the race). Three attempts with the 3 mappings and starting all of them with 22L. Between race and race, I used the restart race option (same conditions), and the mapping was changed with the ICM, before the green lights.

As I expected, with normal and lean maps, I was slower that with rich map. But surprisingly the fuel consumption was higher with normal and lean map. I finished the rich map race with more fuel than with the other two. These are the results (snapshots taken just before crossing the finish line):

250637

250638

250639

250640

So the engine mapping only affects the performance of the engine, not the fuel consumption (at least with this car). The comsumtion is higher with lean map, so it's useles for fuel management. The rich map is the map with lower consumption. :ambivalence:

This is a circuit with all the time flat and top speed. But the engine mapping affects even more to acceleration than top speed. The top speed difference is 7-8Kmh, and this is 1 second per lap at Indianapolis. But you can see, that in the first lap of acceleration (from 120khm in red light), the difference in this lap was 1,6”, bigger than any other lap. So in stop and go circuits, the gap in terms of performance would be huge, without any fuel savings.

I think that the devs must look into this, because is obviously wrong.

eracerhead
24-02-2018, 23:46
I noticed a while ago that in the car I usually drive in leagues, each setting accounts for a roughly 18hp jump in power. To be honest, I've never had to resort to changing it during a race. However, if there's no fuel economy in using either setting then that should definitely be addressed.

TexasTyme214
25-02-2018, 01:15
I've seen this in the past myself. To me, it seems like only power level is changing, not the fuel consumption. Thus, you spend more fuel per lap on lean mix because you are getting around the track slower while the fuel economy is the same.

I'd like to see that it's more efficient to use a lean mix, but the obvious trade off would be track position. Example:

Rich - 100% power - 100% fuel consumption
Normal - 95% power - 87.5% fuel consumption
Lean - 90% power - 75% fuel consumption

Asturbo
25-02-2018, 07:09
I'd like to see that it's more efficient to use a lean mix, but the obvious trade off would be track position. Example:

Rich - 100% power - 100% fuel consumption
Normal - 95% power - 87.5% fuel consumption
Lean - 90% power - 75% fuel consumption
I agree. The gain in consumption should be higher than the loss of performance for efficience.

milliotseb
25-02-2018, 07:46
I use the fuel mapping to adjust the time gap to 2nd position when I am leading the race.
I also agree that fuel mapping should have an impact on fuel consumption. Did you tried with another car to verify if the issue is only related to the ferrari only?

Asturbo
25-02-2018, 08:04
I've noticed with an LPM car. So I tested with the most popular car in PC2. I'll try to confirm with more cars.

ProDriver
25-02-2018, 08:46
That is a bug, and should be fix in a patch.
In ps4 is the same bug.

dhfool
25-02-2018, 09:02
It was working correctly /save fuel-less power/ at least on Vantage GT3 before last patch. Now it seems it is not working as it should. I didn't do any research, but it is highly possible that it is really a bug...

Asturbo
25-02-2018, 09:43
It was working correctly /save fuel-less power/ at least on Vantage GT3 before last patch. Now it seems it is not working as it should. I didn't do any research, but it is highly possible that it is really a bug...
After your post, I've tested in same condition with the Vantage and, as you said, it looks OK:

Lean Power: 467
Lean Compumption: 15.4L / 1.95L per lap

Rich Power: 521 (+12%)
Rich Compumption: 17.8L / 2.25L per lap (+15%)

It's looks that with some cars is correct, but others don't...

davidt33
25-02-2018, 10:50
What is this Lean/Normal/Full fuel mapping about? I've never seen this or realised it was an option in the game. I always thought there was just "fuel" and that one just put in the amount of fuel accordingly and so consumed. Or is it a PC only thing?

fbetes
25-02-2018, 10:54
It's bugged. I've been testing this morning (PS4) and the OP is right: engine mapping doesn't affect to fuel consumption.

Asturbo
25-02-2018, 11:14
What is this Lean/Normal/Full fuel mapping about? I've never seen this or realised it was an option in the game. I always thought there was just "fuel" and that one just put in the amount of fuel accordingly and so consumed. Or is it a PC only thing?
It's an option in some cars to change the engine mapping. You can change it with the ICM while driving or in the setup of the car. I don't know the exact words used in english for the maps, it could be different as posted...


It's bugged. I've been testing this morning (PS4) and the OP is right: engine mapping doesn't affect to fuel consumption.
Which car? I've noticed that some cars works as expect, but most of them don't...

Asturbo
25-02-2018, 11:20
Toyota LMP1 [OK]

Lean Power: 458
Rich Power: 513 (+12%)
Lean Cons: 1.875L per lap
Rich Cons: 2.33L per lap (+24.6%)

Ferrari 488 GTE [WRONG]

Lean Power: 473
Rich Power: 511 (+8%)
Lean Cons: 1.89L per lap
Rich Cons: 1.86L per lap (-1.5%)

Ferrari F50 [LOW]

Lean Power: 526
Rich Power: 600 (+14%)
Lean Cons: 2.20L per lap
Rich Cons: 2.37L per lap (+7%)

McLaren GT3 [VERY WRONG]

Lean Power: 443
Rich Power: 471 (+6%)
Lean Cons: 1.97L per lap
Rich Cons: 1.90L per lap (-3%)

Formula Renault [LOW]

Lean Power: 451
Rich Power: 525 (+16%)
Lean Cons: 2,55L per lap
Rich Cons: 2.77L per lap (+8%)

911 GT1-98 [WRONG]

Lean Power: 490
Rich Power: 530 (+8%)
Lean Cons: 2,27L per lap
Rich Cons: 2.22L per lap (-2%)


Correct Cars tested: Toyota LMP1, Vantage GT3
Lean too small effect: Ferrari F50, Formula Renault
Wrong Cars tested: Ferrari 488 GT3, Ferrari 488 GTE, McLaren GT3, 911GT1

ATM the cars I've test, only the Toyota and the Vantage work as it should. The fuel saving with lean is more than proportional to the power loss.
Other cars like like F50 and FR, the lean map reduces the fuel consumption, but the power loss is bigger. The engine is still more efficient with rich map
Other like McLaren GT3 are specially wrong. From lean, you can increase you power a 6% and reduce your consumpion a 3% changing the map to rich.

peterCars
26-02-2018, 02:02
it's lean and mean then for the most part.

KANETAKER
26-02-2018, 07:16
Toyota LMP1 [OK]

Lean Power: 458
Rich Power: 513 (+12%)
Lean Cons: 1.875L per lap
Rich Cons: 2.33L per lap (+24.6%)


In the case of the Toyota LMP1 car, I can corroborate that yes there is a saving of fuel when using the Lean map along with a loss of performance / speed, which is more noticeable in the long straights. Although there is missing the fuel consumption data with the Normal map. Also, I'm not sure if in the case of the Rich Map it is normal for the fuel in the Toyota to only reach for 8 laps (at LeMans) instead of the 9 laps it indicates in the setup, or if that also depends on the type of setup and if you push the LMP1 car too hard doing qualifying laps during a entire stint.

Asturbo
26-02-2018, 07:51
In the case of the Toyota LMP1 car, I can corroborate that yes there is a saving of fuel when using the Lean map along with a loss of performance / speed, which is more noticeable in the long straights. Although there is missing the fuel consumption data with the Normal map. Also, I'm not sure if in the case of the Rich Map it is normal for the fuel in the Toyota to only reach for 8 laps (at LeMans) instead of the 9 laps it indicates in the setup, or if that also depends on the type of setup and if you push the LMP1 car too hard doing qualifying laps during a entire stint.
The Toyota is the most correct car I've tested until now. You can save up 25% fuel changing map to lean, and the power gets reduced 12%. In other cars the power loss is higher than the fuel savings. That's incorrect, but in extreme situations, could help. But the worst are the cars that with lean map, waste more fuel than with rich map, like the McLaren, the 911GT1 or the Ferraris GTx. That is totaly wrong.

OddTimer
26-02-2018, 10:13
The Toyota is the most correct car I've tested until now. You can save up 25% fuel changing map to lean, and the power gets reduced 12%. In other cars the power loss is higher than the fuel savings. That's incorrect, but in extreme situations, could help. But the worst are the cars that with lean map, waste more fuel than with rich map, like the McLaren, the 911GT1 or the Ferraris GTx. That is totaly wrong.

And I thought I was doing something wrong...had noticed fuel consumption was always the same in GT3 awhile back. Great job Asturbo! hopefully Devs will fix it.

Casey Ringley
26-02-2018, 13:54
...test data...

This is great testing. I think you've discovered that the issue is with turbocharged cars only. Our fuel consumption model is very simple; it just looks at manifold pressure+rpm and sucks fuel from the tank in relation to those factors. Could be some kind of disconnect between manifold pressure and throttle input signals when using turbo cars and non-100% fuel map. Clearly the power side of the model is working as <100% fuel map gives less than maximum manifold pressure and therefore less power, but it should automatically also use less fuel as a result. We'll investigate the bug.

Asturbo
26-02-2018, 14:03
This is great testing. I think you've discovered that the issue is with turbocharged cars only. Our fuel consumption model is very simple; it just looks at manifold pressure+rpm and sucks fuel from the tank in relation to those factors. Could be some kind of disconnect between manifold pressure and throttle input signals when using turbo cars and non-100% fuel map. Clearly the power side of the model is working as <100% fuel map gives less than maximum manifold pressure and therefore less power, but it should automatically also use less fuel as a result. We'll investigate the bug.
Thank you for you interest Casey. I was also thinking about the turbocharger, but I couldn't confirm yet. Please, keep us informed with your researchs.

Keena
26-02-2018, 14:20
Would short shifting be a better way of saving fuel than selecting lean mixture then? Something to bear in mind and perhaps run a comparison. I'm away from my pc at the moment..

Sessionerror
26-02-2018, 14:23
Would short shifting be a better way of saving fuel than selecting lean mixture then? Something to bear in mind and perhaps run a comparison. I'm away from my pc at the moment..

Short shifting and especially coasting are quite efficient when it comes to fuel saving. Only used those methods and never the fuel mapping to save fuel...and I was able to save quite a lot in a couple of races ;) Having an efficient and working (in terms of fuel saving) fuel mapping would be more comfortable though :D

Asturbo
26-02-2018, 14:31
Obviously shortshifting and lift&run technics would help to reduce fuel consumption, but all together with a lean engine mapping will improve even more the fuel saving.

Invincible
26-02-2018, 15:19
Obviously shortshifting and lift&run technics would help to reduce fuel consumption, but all together with a lean engine mapping will improve even more the fuel saving.

Also with the lean map you don't have to worry about shifting early enough. On the downside you can't switch back to normal that fast if needed for one straight. When you manage your shifting and coast, you still have all the power available when you need it.

Keena
26-02-2018, 17:06
Also with the lean map you don't have to worry about shifting early enough. On the downside you can't switch back to normal that fast if needed for one straight. When you manage your shifting and coast, you still have all the power available when you need it.

Good point. I remember I ran out of fuel once despite all my best efforts at Oulton park. I coasted across the line and the car stopped about 20 metres further on. Colin Chapman would've been proud ;)

WGIstation6a
26-02-2018, 17:55
Unrelated, but semi related: it would be nice to be able to hot key the fuel map. It would make selecting the map per section of track much easier.

F1_Racer68
26-02-2018, 17:58
Lean mapping (when working proper;ly) should only save a small amount of fuel per lap. It will only allow you to gain a few laps per fuel stint compared to rich.

And it will only do that if you run the lean setting from the first lap on. IRL, those mappings do not have a massive effect on mileage, which is why you will see/hear drivers be instructed to change those mappings as they exit the pits.

Do not expect to be able to stretch your fuel 3 laps longer if you realize with 8 laps left in the race that you only have 5 laps of fuel left. That will simply NEVER happen.

Now, the fact that it seems to work correctly in some cars, but not in others is definitely an issue.

F1_Racer68
26-02-2018, 17:58
Unrelated, but semi related: it would be nice to be able to hot key the fuel map. It would make selecting the map per section of track much easier.

I second this.... Fuel Map, TCS Map and ABS map should be able to have buttons mapped to them. If it can be adjusted in the car by the driver, it should be available to map to a button box.

Asturbo
26-02-2018, 19:00
Some adittional cars tested:

250758

ermo
26-02-2018, 19:34
What is this Lean/Normal/Full fuel mapping about? I've never seen this or realised it was an option in the game. I always thought there was just "fuel" and that one just put in the amount of fuel accordingly and so consumed. Or is it a PC only thing?

During a 4 stroke gasoline Otto engine cycle (intake-stroke, compression-stroke, power-stroke, exhaust-stroke), only the power-stroke delivers actual motive force. The amount of pressure created in the cylinder after the ignition is by and large controlled by how much air you manage to shove/suck into your cylinder.

For the air-fuel mixture to be combustible in "traditional" engines, you need to stay within roughly 10-15% of the stoichiometric (1 to 1) air-fuel ratio, which is 14.7 kg of air per 1 kg of fuel if you want to achieve a 100% burn of all injected fuel (in theory).

If you ingest the same amount of air, but inject slightly less fuel (for instance 0.9 kg fuel per 14.7 kg air), you make the air-fuel mixture "leaner"' This makes for lower combustion temperatures, which makes for lower cylinder pressure, which makes for less torque and (since power is a function of torque and RPM) less power at any given RPM.

If instead, you inject slightly more fuel (say, 1.11 kg fuel per 14.7 kg of air), you make the air-fuel mixture "richer". In the real world, this leads to being able to create slightly higher combustion temperatures (and hence more power and torque) AND results in slightly better cooling, since the hot intake charge will tend to expend more energy vaporising the extra fuel and thus cooling itself in the process (only vaporised fuel will combust, which is why it is injected as a fine mist in the first place).

For turbo engines, the manifold overpressure (boost) allows you to shove more air in, and as a consequence, burn more fuel and thus create more heat and higher cylinder pressure, which then gives you more torque and more power for the same cylinder volume.

Anyway, to measure this in the real world, the engine control unit combines sensor readings from the manifold pressure/airflow/temperature sensors, the throttle position sensor and the crankshaft position sensor and then injects the appropriate amount of fuel, based on a lookup-table called the fuel map (with some extra corrections that adapt to temperature, driving pattern, small variations in cylinder pressure which can be measured via cross-checking the crankshaft position sensor rate of acceleration with the spark event for a given cylinder).

In engine control units used by tuners and in racing, you can have more than one such lookup-table or "fuel map" and switch between them as appropriate.

In this case, Casey suspects that the simulation model used for fuel consumption has a bug where turbo cars don't see any decrease in fuel consumption when the lean map (less than 1 kg of fuel per 14.7 kg of air) is chosen in the "In Car Menu (ICM)", but the power still drops off.

I hope that made at least a little sense?

AbeWoz
26-02-2018, 19:40
Some adittional cars tested:

250758

thats very useful for the TS040 to not use KERS energy at 'full throttle' since changing the fuel map in-game really only limits the throttle position. You can see this on the throttle bar on the on-screen APP display.

Asturbo
26-02-2018, 20:41
thats very useful for the TS040 to not use KERS energy at 'full throttle' since changing the fuel map in-game really only limits the throttle position. You can see this on the throttle bar on the on-screen APP display.
Yes, I've notice that also, and I'm afraid it is one of the problems.

Looks that the normal and lean map blocks the maximun travel of the gas pedal. You can see in the captures of my first post, where the gas is at 90% of the travel at lean, and in normal is at 95% (green line).

Probably changing the fuel map is the same effect than not pressing the pedal until the floor (or puting a table under the pedal). I was expecting that the engine mapping would act over the fuel mixture, the turbo pressure, ignition or electronics (as IRL), not over the pedal travel. Anyway if the mapping works in this way in PC2, it's not easy to understand how a car at 90% of the throttle, wastes more fuel than same car at 100%.

Hope that Casey could clarify this question.

TexasTyme214
27-02-2018, 00:02
I always saw it as the cars not using any less fuel instantaneously with less power. Now, you are spending more time to get down there straights as the engine is spending fuel at the same rate. In other words, you are spending more time on the throttle per lap than you are on rich fuel mix. This is resulting in slower lap times and more fuel used.

It looks like the Toyota and the Vantage based on the data above are getting more efficient with leaner mixes. I wonder why the GT1 cars are struggling with this, including the non aspirated cars.

Asturbo
27-02-2018, 11:53
In street cars the fuel consumption depends of deifferent factors. The most important are:

-% of acelerator pressed
-RPM of the engine
-Engine mapping

In example if modern cars you have maps like ECO/NORMAL/SPORT. The sport mode gives you more power but it's the less efficient. Anyway, if you push the pedal to the floor with ECO, the fuel consumption is lower than doing the same in SPORT mode (but loosing performance). What we need to know is if the maps in PC2 works in this way, or is only a limit in the pedal travel, as it looks like.

PS1: Obviusly the driving style is the most important, but I'm imagining a drag race for example full gas and changing at same RPMs, avoiding driver skills.
PS2: IRL there're other factors like the weight loaded in the car, opened windows, or the use of AC, but not relevant for this issue.

sas5320
06-03-2018, 14:41
Lean mapping (when working proper;ly) should only save a small amount of fuel per lap. It will only allow you to gain a few laps per fuel stint compared to rich.

And it will only do that if you run the lean setting from the first lap on. IRL, those mappings do not have a massive effect on mileage, which is why you will see/hear drivers be instructed to change those mappings as they exit the pits.

Do not expect to be able to stretch your fuel 3 laps longer if you realize with 8 laps left in the race that you only have 5 laps of fuel left. That will simply NEVER happen.

Now, the fact that it seems to work correctly in some cars, but not in others is definitely an issue.
Though generally I agree with you that it cannot perform miracles, in Indycar testing fuel consumption is a big part of the race strategy and drivers are being constantly instructed to hit a "fuel number" (fuel usage per lap) by their race engineers during the race. Often you can hear in Indycar radio drivers are arguing with their race strategists, so in some motorsports this is a big function. Glad when Casey/physics team will have it fixed up.

F1_Racer68
06-03-2018, 20:43
Though generally I agree with you that it cannot perform miracles, in Indycar testing fuel consumption is a big part of the race strategy and drivers are being constantly instructed to hit a "fuel number" (fuel usage per lap) by their race engineers during the race. Often you can hear in Indycar radio drivers are arguing with their race strategists, so in some motorsports this is a big function. Glad when Casey/physics team will have it fixed up.

Totally agree, but again, look at WHEN those IndyCar drivers are being told what numbsrs to hit. It is at the START of a fuel stint, or early on in it. They are not being asked to.adjust it near the end of a stint, because by then it is pointless as there are not enough laps left in the stint to make saving worth while, or they simply won't be able to save enough to make a difference.

IndyCar fuel consumption numbers (as with sportscar) are based on known usage rate in each mixture, and a target number of laps that the teams wants to achieve on that fuel load.

g.stew
06-03-2018, 20:56
Yes, I've notice that also, and I'm afraid it is one of the problems.

Looks that the normal and lean map blocks the maximun travel of the gas pedal. You can see in the captures of my first post, where the gas is at 90% of the travel at lean, and in normal is at 95% (green line).

Probably changing the fuel map is the same effect than not pressing the pedal until the floor (or puting a table under the pedal). I was expecting that the engine mapping would act over the fuel mixture, the turbo pressure, ignition or electronics (as IRL), not over the pedal travel. Anyway if the mapping works in this way in PC2, it's not easy to understand how a car at 90% of the throttle, wastes more fuel than same car at 100%.

Hope that Casey could clarify this question.

Ah, that makes sense now. I was driving in heavy rain and had my fuel mix on lean and noticed the pedal wasn't filling all the way on the speedo. When I look at the telemetry view, my pedal was filling the whole bar. I thought it was just a visual thing but that makes sense now. Will be useful as a visual indicator of the fuel mix.

Keena
06-03-2018, 21:01
Totally agree, but again, look at WHEN those IndyCar drivers are being told what numbsrs to hit. It is at the START of a fuel stint, or early on in it. They are not being asked to.adjust it near the end of a stint, because by then it is pointless as there are not enough laps left in the stint to make saving worth while, or they simply won't be able to save enough to make a difference.

IndyCar fuel consumption numbers (as with sportscar) are based on known usage rate in each mixture, and a target number of laps that the teams wants to achieve on that fuel load.

I'm wondering if the fuel flow rate is not a fixed number, but depends on weight. The heavier the car, the greater the amount of fuel required to get it around a lap, so if your car is full of fuel, the amount of fuel you'd burn to get around a lap would be greater than if you were much lighter of fuel. Incredible complexity in the fuel model if so, but I rather doubt it. I wish as well that there was more strategy involved with fuel stops ie is it worth running lighter on fuel and going faster, or fuelling up and not stopping as much. I hear people on here fretting about an extra few kilos but from what I can tell it makes an insignificant difference to just chuck on an extra couple of laps of fuel to be sure of finishing.. just some idle thoughts.

TexasTyme214
06-03-2018, 21:23
I'm wondering if the fuel flow rate is not a fixed number, but depends on weight. The heavier the car, the greater the amount of fuel required to get it around a lap, so if your car is full of fuel, the amount of fuel you'd burn to get around a lap would be greater than if you were much lighter of fuel. Incredible complexity in the fuel model if so, but I rather doubt it. I wish as well that there was more strategy involved with fuel stops ie is it worth running lighter on fuel and going faster, or fuelling up and not stopping as much. I hear people on here fretting about an extra few kilos but from what I can tell it makes an insignificant difference to just chuck on an extra couple of laps of fuel to be sure of finishing.. just some idle thoughts.

I find the latter to be very important if the car is light. The Formula A for example is very sensitive to how much fuel is in the car, and I find that tenths can be found by removing a couple laps worth of fuel. I don't think GT cars are very sensitive to this.

I have not tested fuel economy vs onboard fuel. That could be an interesting test.

g.stew
06-03-2018, 21:28
I find the latter to be very important if the car is light. The Formula A for example is very sensitive to how much fuel is in the car, and I find that tenths can be found by removing a couple laps worth of fuel. I don't think GT cars are very sensitive to this.

I have not tested fuel economy vs onboard fuel. That could be an interesting test.

Have you tried this after the latest patch? There was something in the notes about reducing the fuel tank capacity on formula A to a more reasonable level. I haven't tried it since the patch though and wonder if it makes a difference there.

HockeyNick30
06-03-2018, 23:09
Short shifting and especially coasting are quite efficient when it comes to fuel saving. Only used those methods and never the fuel mapping to save fuel...and I was able to save quite a lot in a couple of races ;) Having an efficient and working (in terms of fuel saving) fuel mapping would be more comfortable though :D

This method has saved my bacon a couple of times when I under-fueled the car toward the end of a race ;)

TexasTyme214
11-04-2018, 22:30
I did a quick test with the Porsche 911 GT1 and Aston GTE at Daytona Oval. Turbo cars are not saving fuel with lean fuel mapping in Patch 5.0, but the Aston Martin showed a reasonable decrease in fuel consumption.

Hammerpgh
21-05-2018, 12:41
This is a bug bear of mine too... was about to post a new thread but found this one so am posting my findings here:-

I donít believe the different fuel mixes we get access to from the ICM actually make any difference to the fuel rate, at least in the Indycar they do not seem to change this. I tested this for an Indycar League I race in at Long Beach and again last night at COTA. On both occasions moving down from Rich mixture to either Normal or Lean seemed to have no benefit. My lap times dropped slightly but the fuel rate per lap stayed pretty much the same give or take 5/hundredths to 1/tenth of a litre.

I have only tested this in the Indycar but was just wondering whether anyone else had found the same? I used rsDash to see the fine details but by manually checking on the HUD it still confirmed the lack of fuel saving generated by the lower mixes. Unfortunately the cars motec is completely wrong in the Indycar when it comes to fuel usage, showing around 1.16 litres per lap from memory which is about 3 litres shy of what it should be.

Cheers
2018 Indycar League on Project Cars 2
http://consoleracing.boards.net/board/89/project-cars-indycar-league-2018

Asturbo
21-05-2018, 12:58
Nathan said that it's fixed internally, so expect that will be avaliavable in next patch. As you said, ATM fuel mapping doesn't work with most cars. It only reduces power. Let's be patient.


The relative HUD issue has also been improved, and the fuel mapping issue has now been fixed.

Hammerpgh
22-05-2018, 23:07
This is great testing. I think you've discovered that the issue is with turbocharged cars only. Our fuel consumption model is very simple; it just looks at manifold pressure+rpm and sucks fuel from the tank in relation to those factors. Could be some kind of disconnect between manifold pressure and throttle input signals when using turbo cars and non-100% fuel map. Clearly the power side of the model is working as <100% fuel map gives less than maximum manifold pressure and therefore less power, but it should automatically also use less fuel as a result. We'll investigate the bug.

Any update on this Casey, that post was three months ago now and this problem is still very much apparent.

Also the IndyCar fuel display on the motec doesn't work properly as it shows the incorrect fuel usage. For example at COTA it shows 1.16 when in reality it is about 4.3

sas5320
23-05-2018, 00:49
They said they fixed fuel maps in the next coming patch.

Not sure about the display issue however

Ofnir4
23-05-2018, 02:05
Any update on this Casey, that post was three months ago now and this problem is still very much apparent.

Also the IndyCar fuel display on the motec doesn't work properly as it shows the incorrect fuel usage. For example at COTA it shows 1.16 when in reality it is about 4.3

It's not really a fuel usage issue, it's an unit of measurement issue. Whatever system you use (metric or imperial), the Indycar will show you everything in gallons. The Esperante GT1 was (or maybe still is, haven't checked)like that, and probably a lot of "US built and operated" cars.

Hammerpgh
23-05-2018, 08:45
This is great testing. I think you've discovered that the issue is with turbocharged cars only. Our fuel consumption model is very simple; it just looks at manifold pressure+rpm and sucks fuel from the tank in relation to those factors. Could be some kind of disconnect between manifold pressure and throttle input signals when using turbo cars and non-100% fuel map. Clearly the power side of the model is working as <100% fuel map gives less than maximum manifold pressure and therefore less power, but it should automatically also use less fuel as a result. We'll investigate the bug.


It's not really a fuel usage issue, it's an unit of measurement issue. Whatever system you use (metric or imperial), the Indycar will show you everything in gallons. The Esperante GT1 was (or maybe still is, haven't checked)like that, and probably a lot of "US built and operated" cars.

Thanks for the explanation, so a similar thing to the whole psi/bar issue with tyre pressures in the pit strategy... that being the case though it's still incorrect. The car was using 4.3 litres per lap which equates to 0.95 gallons which is not what the display was showing.

Hammerpgh
23-05-2018, 08:46
They said they fixed fuel maps in the next coming patch.

Not sure about the display issue however

Thanks for that.. where was that information given?

Asturbo
23-05-2018, 08:48
Thanks for that.. where was that information given?
http://forum.projectcarsgame.com/showthread.php?62712-Unofficial-issue-list-Post-Patch-5-0&p=1510026&viewfull=1#post1510026

Ofnir4
23-05-2018, 11:13
Thanks for the explanation, so a similar thing to the whole psi/bar issue with tyre pressures in the pit strategy... that being the case though it's still incorrect. The car was using 4.3 litres per lap which equates to 0.95 gallons which is not what the display was showing.

You sophisticated British have a different gallon to the US.;) With the US gallon, the conversion is spot on.

F1_Racer68
23-05-2018, 12:15
Thanks for the explanation, so a similar thing to the whole psi/bar issue with tyre pressures in the pit strategy... that being the case though it's still incorrect. The car was using 4.3 litres per lap which equates to 0.95 gallons which is not what the display was showing.

As Ofnir4 stated, it's displaying a U.S. gallon on the IndyCar dash/wheel. That is 3.79 (3.7854 technically) Litres per U.S. gallon. If you do the math on that it should be pretty accurate.

4.3 Litres translates to 1.1359 U.S. gallons.

Hammerpgh
23-05-2018, 21:08
As Ofnir4 stated, it's displaying a U.S. gallon on the IndyCar dash/wheel. That is 3.79 (3.7854 technically) Litres per U.S. gallon. If you do the math on that it should be pretty accurate.

4.3 Litres translates to 1.1359 U.S. gallons.

Ok many thanks. I wasn't are there was a difference between a UK and US gallon. That clears it up nicely.

Asturbo
04-06-2018, 21:08
I've tested only the Ferrari GT3 & McLaren GT3 (the worst car reported in this thread), and the issue was improved.

Now, both wastes more fuel in rich than in lean. That is an improvement because previous this patch both cars wastes more fuel on lean. But I think that the fuel saving looks the same of the power loss (for this car) and I think that must be more than proportional. Anyway this needs deeper test, and more data of different cars, but at least looks that after the patch you always save fuel changing to lean map.

KANETAKER
04-06-2018, 21:31
I've tested only the Ferrari GT3 & McLaren GT3 (the worst car reported in this thread), and the issue was improved.

Now, both wastes more fuel in rich than in lean. That is an improvement because previous this patch both cars wastes more fuel on lean. But I think that the fuel saving looks the same of the power loss (for this car) and I think that must be more than proportional. Anyway this needs deeper test, and more data of different cars, but at least looks that after the patch you always save fuel changing to lean map.

In the case of the LMP1 (for now I have only tested the TS040) it seems that the fuel map is also linked to the quantity and speed of consumption of the KERS.

Tar Heel
04-06-2018, 21:42
In the case of the LMP1 (for now I have only tested the TS040) it seems that the fuel map is also linked to the quantity and speed of consumption of the KERS.

Stint length improve at all?

TexasTyme214
04-06-2018, 23:51
Stint length improve at all?

I just ran this test really quickly at LM in the Toyota TS040 with "full simulation" settings except TCS was off.

Rich: 3:19s, 7.2L/lap, ~9.3 laps per stint, 520hp
Normal: 3:25s, 7.0L/lap, ~9.5 laps per stint, 495hp

Note: when I used normal, I switched the engine back to rich mix after KERS was depleted from Arnage to the end of the lap.

It's still more efficient to use rich mix, at least on this car. I don't see the purpose, in terms of a real race scenario, why one would not use rich if they were trying to win a longer race on this car. FWIW, I think the car has a considerable lower fuel consumption rate in normal compared to rich, but I think because the KERS is slowing the car down so much, you spend more time on the straights, reducing the amount of fuel saved. In my mind, these leaner mixes should guarantee us the 12-13 lap stints these cars were able to do at a pace closer to the rich mix.

Tar Heel
05-06-2018, 00:05
I just ran this test really quickly at LM in the Toyota TS040 with "full simulation" settings except TCS was off.

Rich: 3:19s, 7.2L/lap, ~9.3 laps per stint, 520hp
Normal: 3:25s, 7.0L/lap, ~9.5 laps per stint, 495hp

Note: when I used normal, I switched the engine back to rich mix after KERS was depleted from Arnage to the end of the lap.

It's still more efficient to use rich mix, at least on this car. I don't see the purpose, in terms of a real race scenario, why one would not use rich if they were trying to win a longer race on this car. FWIW, I think the car has a considerable lower fuel consumption rate in normal compared to rich, but I think because the KERS is slowing the car down so much, you spend more time on the straights, reducing the amount of fuel saved. In my mind, these leaner mixes should guarantee us the 12-13 lap stints these cars were able to do at a pace closer to the rich mix.

That's kinda what my quick testing with the Audi and Toyota this afternoon showed too. My question is why spend the time coding a link between KERs and the fuel mapping which basically gives the player manual control of the KERs (albeit through a tedious process) instead of just mapping a manual KERs button? I know that isnt how it worked in RL but I wouldn't expect the RL custom per track deployment to be in the game.

I also agree on the stint lengths. The Audi especially with it's much smaller fuel tank. I can get about 6.4L per lap, but the RL car averaged closer to 4L per lap with low 3:20s as their pace.

Also I realize the 2014 LMP1 won't be as tantalizing once the DLC drops but that doesn't mean I want them to fade out of existence

TexasTyme214
05-06-2018, 01:36
I agree that it's tedious to switch mixes multiple times over a lap. It's actually less work to just lift my foot in some spots.

I did this test again in the Nissan GTP:
Rich: 900hp, 12L/lap, 10 laps per stint, 205mph or so
Lean: 820hp, 11.7L/lap, 10 laps again, 187 mph

So again, the car is too slow to the point that you're not saving fuel but falling behind quickly. I feel like this some calculation that happens in the background organically, but I wouldn't be opposed to fuel mixes having a "canned" effect on the engine in the end. I'd like to see something along the lines of:

Rich: 100% power/100% fuel consumption
Normal: 98% power/90% fuel consumption
Lean: 96% power/80% fuel consumption

Here, efficiency skyrockets as you lower the mix, but the power loss hurts a little you every single lap.

Tar Heel
05-06-2018, 01:52
I agree that it's tedious to switch mixes multiple times over a lap. It's actually less work to just lift my foot in some spots.

I did this test again in the Nissan GTP:
Rich: 900hp, 12L/lap, 10 laps per stint, 205mph or so
Lean: 820hp, 11.7L/lap, 10 laps again, 187 mph

So again, the car is too slow to the point that you're not saving fuel but falling behind quickly. I feel like this some calculation that happens in the background organically, but I wouldn't be opposed to fuel mixes having a "canned" effect on the engine in the end. I'd like to see something along the lines of:

Rich: 100% power/100% fuel consumption
Normal: 98% power/90% fuel consumption
Lean: 96% power/80% fuel consumption

Here, efficiency skyrockets as you lower the mix, but the power loss hurts a little you every single lap.

Agreed, reality is I can achieve the same kinds of fuel savings and from my testing today (faster times) lifting or not using full throttle in areas than switching fuel mixtures and what not. The only thing I can think that the fuel mixes help with (and this is anecdotal since I haven't tested it) is that the lean wears the engine down much slower than rich. Again no proof it would need to be tested, but I did notice the engine picking up less damage as I was running lean more often.

KANETAKER
05-06-2018, 01:58
Fuel consumption does not only depend on the fuel map you use, but also on the setup of the car and how hard you are pushing during a race.

Taking as reference the TS040 in LeMans, in races with deactivated mechanical faults and optimal temperature conditions, when I push the car very hard, lap after lap doing qualifying times, the fuel only reaches me to complete 8 laps. But instead, if the race conditions are more realistic (mechanical failures activated, climate and temperature variable including cold) I am not able to push the car as hard as I would like, and then I can complete 9 laps before refueling.

TexasTyme214
05-06-2018, 02:29
Fuel consumption does not only depend on the fuel map you use, but also on the setup of the car and how hard you are pushing during a race.

Taking as reference the TS040 in LeMans, in races with deactivated mechanical faults and optimal temperature conditions, when I push the car very hard, lap after lap doing qualifying times, the fuel only reaches me to complete 8 laps. But instead, if the race conditions are more realistic (mechanical failures activated, climate and temperature variable including cold) I am not able to push the car as hard as I would like, and then I can complete 9 laps before refueling.

I've noticed the same thing. I typically run the car with all the damage and wear on, so I'm used to seeing the 9 laps, one less than some Group C cars lol.

Tar Heel
05-06-2018, 04:06
I've noticed the same thing. I typically run the car with all the damage and wear on, so I'm used to seeing the 9 laps, one less than some Group C cars lol.

The idea of the fuel saving in the ICM sounds great on paper, but I feel controlling the throttle generates the same effect since the fuel mixtures are really tied to the max amount of throttle input required. Along with that even if you can save a little fuel, the time hits seem to be too great to make them worth their trouble.

More testing is needed to see how the different fuel mixtures impact the engine damage (if at all), but as of now rich seems like a no brainer IMO.

Now the other thing I am curious at testing is the impact of turbo boost and how that impacts lap times and fuel savings. It will be fun to test out all the new cars :)

Hammerpgh
30-08-2018, 13:25
Just wondering where we are on this and whether there is likely to be anything done about it in a future patch... I have re-read this entire thread and also the one where it is mentioned that the fuel mapping has been fixed (http://forum.projectcarsgame.com/showthread.php?62712-Unofficial-issue-list-Post-Patch-5-0&p=1510026&viewfull=1#post1510026 - The relative HUD issue has also been improved, and the fuel mapping issue has now been fixed.) but I still see no difference between the different fuel settings at least in the Indycar.

Asturbo
30-08-2018, 15:58
I've only tested a few cars after patch to verify this issue, and I also think that it is not 100% fixed. With most of the cars, the fuel eficiency is the same in rich than lean. Obviously after patch, in lean map the consumption is lower, but only because you're going slower (not full gas). But now it’s not as serious problem as before when the car in lean wasted more fuel than in rich.

For these cars, the engine mapping is really an acelerator mapping that blocks the last travel of the gas pedal. I.E. at 50% of throttle, the fuel consumption is the same with the any engine mapping. Some cars looks working as it should, but are the minority. I don’t tested with Indy cars.

Hammerpgh
30-08-2018, 17:20
Do we know if any more patches are due for the game or are we done now?

Asturbo
30-08-2018, 17:28
Yes, a patch is coming soon.

Tar Heel
31-08-2018, 17:29
I've only tested a few cars after patch to verify this issue, and I also think that it is not 100% fixed. With most of the cars, the fuel eficiency is the same in rich than lean. Obviously after patch, in lean map the consumption is lower, but only because you're going slower (not full gas). But now it’s not as serious problem as before when the car in lean wasted more fuel than in rich.

For these cars, the engine mapping is really an acelerator mapping that blocks the last travel of the gas pedal. I.E. at 50% of throttle, the fuel consumption is the same with the any engine mapping. Some cars looks working as it should, but are the minority. I don’t tested with Indy cars.

I just don't see a point to the system in its current state. It is way easier and probably more efficient to just lift and coast to save fuel than it is to change fuel mixture and slow the car.

Asturbo
31-08-2018, 18:05
I just don't see a point to the system in its current state. It is way easier and probably more efficient to just lift and coast to save fuel than it is to change fuel mixture and slow the car.

Obviously the driver skills is one important factor in fuel consumption but not the only one. Fuel mapping is other thing that allows fuel saving in real life:

"The fuel map switch allows the driver to adjust the fuel mapping of the engine to increase fuel mileage or to increase power. There are a number of settings available including full rich, where the engine produces maximum power but uses more fuel.

There is also a lean setting which uses less fuel but produces less power. During caution periods the drivers will switch to the leanest mixture to increase fuel economy."


https://www.youtube.com/watch?v=cfrh56ZUEzA

Source: https://jalopnik.com/heres-what-all-the-buttons-on-an-indycar-steering-wheel-1779388708

Tar Heel
31-08-2018, 19:19
Obviously the driver skills is one important factor in fuel consumption but not the only one. Fuel mapping is other thing that allows fuel saving in real life:

"The fuel map switch allows the driver to adjust the fuel mapping of the engine to increase fuel mileage or to increase power. There are a number of settings available including full rich, where the engine produces maximum power but uses more fuel.

There is also a lean setting which uses less fuel but produces less power. During caution periods the drivers will switch to the leanest mixture to increase fuel economy."


https://www.youtube.com/watch?v=cfrh56ZUEzA

Source: https://jalopnik.com/heres-what-all-the-buttons-on-an-indycar-steering-wheel-1779388708

Right I understand that, but we don't have cautions, and I think at this point it has been shown that the time you loose per lap isnt worth the fuel you save and that similar fuel savings can occur from simply lifting and coasting.

Their are advantages IRL to fuel mapping, but in PC2 with how it is implemented I havent seen a case where it is worth using

Asturbo
31-08-2018, 19:32
IRL the fuel map it's not only used in cautions.

For example in ovals if you're behind other driver, you could use his sliptream and cruise using a leaner map that allows you give another 2 laps, and perhaps save one pit stop (or saving time, loading less fuel in the pit stop).

Or in F1 they have maps with extra power to overtake. They could't use it in the whole race because the can't complete the race.

Tar Heel
01-09-2018, 03:30
IRL the fuel map it's not only used in cautions.

For example in ovals if you're behind other driver, you could use his sliptream and cruise using a leaner map that allows you give another 2 laps, and perhaps save one pit stop (or saving time, loading less fuel in the pit stop).

Or in F1 they have maps with extra power to overtake. They could't use it in the whole race because the can't complete the race.

Asturbo,

I'm not disagreeing on fuel mappings real life usefulness. I'm saying in game they are not effective in their current state. Throttle control is just as effective and easier to manage.

Asturbo
01-09-2018, 07:17
I'm saying in game they are not effective in their current state. Throttle control is just as effective and easier to manage.
OK, understood now, and agree...

MaximusN
01-09-2018, 09:30
Asturbo,

I'm not disagreeing on fuel mappings real life usefulness. I'm saying in game they are not effective in their current state. Throttle control is just as effective and easier to manage.
IMHO throttle control will always be more effective. Because you decide where you save fuel. Most time is to be gained/lost when accelerating out of corners because you go faster earlier. If you reduce engine power you will already start losing out of corners. On the other hand if you get off throttle at the end of the straight(or even earlier) you will only lose minimal time. But the thing is you have to do it consciously and consistantly whereas if you are on a lean mixture you don't have to think about it. It will raise engine temps though because fuel has cooling properties. So even though you're going slower your engine will run hotter(or as least as hot).