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Nov 24 09 12:21 PM

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This thread is meant for those interested about learning how physics are defined in rFactor's cars.

The following files configure the physics of the car:

(click to get more info about them)

.HDV file. Covers suspensions, aero, AI, pit behaviour, etc.

Engine.ini. Engine.

.TBC file. Tires.

.PM file. Physical model.

Damage.INI. Damage.

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#3 [url]

Dec 26 09 1:29 AM

I checked more or less all the parameters that are documented in the files. But, the cars doesn't work in this way.

Quick example:
I wrote a program to check/change the fuel consumption and the tank capacities that are "strange".

The result of the program is a list of all the cars parameters used for fuel consumption. Based on those parameters, the program calculates the final results (fuel consumption per hour and per 100km).

Example : Mini on Mid Ohio No chicane
Formula to get the amount of liters/hour for each car (found on rsc) :
Cons = Rad * AccelValue * FuelCoef * Duration * 60

Where :
- Cons = the fuel consumption per hour
- Rad the radians based on max engine rev/mn (Rad = MaxRev / (2*3.14159)
- AccelValue = Throttle value (0 to 1)
- Fuel Coef = the value "FuelConsumption=" from the engine.ini file
- Duration = 60 for a minute

Let take the mini with original values:

With an average throttle of 66%, the mini needs 121L/hour ! (On Mid Ohio, the average throttle value is 72-75% with the mini)

If I want to correct this and if I understood the principle, I have to change the "FuelConsumption" value in the engine.ini file.
So, after some talks with a "Racing Mini" Driver, the car shouldn't need more than 25L/hour
So, I just recalculate the new FuelConsumption value to get a final consumption of 25L/hour.


But, I changed this value in the engine.ini file and tested with the Motec (to be sure that everything is OK).
Résult : The Motec result (on 3 laps) is completly different !

For the 3 laps, I have need 321 seconds and 1.24L fuel.
So, 13.9L/H. That's completly different from the goal/real value of 25L/H !

That's why I'm trying to understand why the formula I found on rsc gives me such a big difference (not far from 50%) compared to the Motec...
Maybe the formula is wrong, maybe I did something wrong in my formulas, I don't know... But I hope I could find an explanation in the rsc topic. That's why I'm asking | | ODS on Facebook | Grand Prix Historic ODS

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#5 [url]

Dec 26 09 6:50 PM

Unfortunatly not until now

A few weeks ago (I'm working on fuel consumption and tires wear since 6 weeks) I had no clue about modding. But trying to solve the issues, helps me to find a lot of informations.
But, I tought I have all the needed informations now and just need to use them (correct the fuel tank capacity and the fuel consumption value).
I have now this new issue that the formula and Motec results aren't the same

I do not have any idea now which way to follow to continue my analysis

That's why I request modders help... | | ODS on Facebook | Grand Prix Historic ODS

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#7 [url]

Dec 27 09 2:03 PM

I didn't get to such detail myself!

for 1.0, I simply make the cars run on the only real world track I have checked fuel consumption for myself: Jarama.

Then for some "testing", I used Virtua LM Le Mans with the 911 2.0 and used it as a benchmark, since it should be around 20l-30l/100km and having a 10km per lap almost at full throttle for most of the laptime, I simnply did ten laps to know exactly the fuel consumption, but I don't know if this is any good reference at all.

Your way looks more scientific, but the results as you've said, haven't come together, so AFAIK, can't help you any more than this... sorry!

"Do the suspension adjustable and they will adjust it wrong." - Colin Chapman

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#8 [url]

Dec 27 09 4:26 PM

OK, so, I have to continue to analyse...

I think I will use the Motec i2pro results as reference. Should be the real values. So I assume that the formula given on the rsc forum is wrong.

Only bad new : if I cannot find the FuelConsumption parameter by a mathematic equation but only by Motec, that meens that I will have to drive one more time 15-20 laps with each car to approch the fuel consumption goal value

But one question : I saw in this forum that the FuelConsumption issues were solved.

So, I understood that you fixed the wrong fuel tanks sizes and the fuel consumption. But how did you do that without havin the formula how it's calculated ? | | ODS on Facebook | Grand Prix Historic ODS

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#9 [url]

Dec 27 09 10:08 PM

nope, I didn't say we solved, I said I found a domehow "more realistic" way of measuring the fuel consumption, which was, precisely, as I told you before. Unfortunately, no formulas are known to my knowledge...

"Do the suspension adjustable and they will adjust it wrong." - Colin Chapman

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#10 [url]

Dec 28 09 8:40 AM

I agree, but issue with fuel consumption and tire wearing is a long story
In this topic you said that it will be fixed too. That's what I translated (one year later) as "is fixed now" ;)

If it's not the case, it's not a problem ;)

That just means that I have to continue using my tool to adapt the fuel consumption of the cars to "reality" and our league will use the new version of the mod only in 2011 | | ODS on Facebook | Grand Prix Historic ODS

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#11 [url]

Jan 10 10 2:35 PM

Since those links are not working anymore, use this:

"Do the suspension adjustable and they will adjust it wrong." - Colin Chapman

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#13 [url]

Jul 7 11 2:46 PM

In relation to fuel consumption, and the exponential value maybe the excel spreadsheet I have created may help.

the link is as follows,

Anybody wishing to give feedback on this is welcome.

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#14 [url]

Jul 14 11 7:12 PM

Thanks for sharing! we will check with our numbers and use it when necessary ;)

"Do the suspension adjustable and they will adjust it wrong." - Colin Chapman

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