For those who are familiar with Carp.txt editing, this might be not new to you, as well as some might not agree with the method or calculation I use.
I am just trying to explain (in a more or less simple way) how to re-calculate particular gearing/engine entries (in the Carp.txt) in NFSWizard with the assistance of RealTuner and somewhat realistic data from web resources.
The base for a realistic drivetrain calculation in any cases is a suitable torque curve of the particular car's engine.
The web source I mostly use is automobile-catalogue.com. As you can imagine, saving 'real' torque curve measurements tabs on a web server would cost a lot disk space as well as not every engine's torque curves were being measured or recorded as well. As a matter of fact, the website uses a calculator to generate a torque curve by the basic engine's and drivetrain factory data. As a result, this only a CALCULATED torque curve (and power curve, too), but since NFS HS anyway uses theoretical data it might fit quite well in most of the cases. The website also points out to that fact:
'The Horsepower / Torque Curve below was generated by ... software, based on the factory data'
All I furthermore do is a kind of 'calculating' the given data 'backwards' for NFS' Carp.txt gearing/engine tab entries.
So now to torque curves in general: As I noticed so far, torque curves in many cars are simply wrong.
It seems to me as if some (and as I have to assume, as if some of the NFS' developers, too ..) mistake 'torque' by 'power', 'horsepower'. An average combustion engine produces its maximum torque earlier (depending on) than its power peak (sometimes it is really just a 'peak')
If you compare the different curves (wykres_power.php.jpg): the Countach's torque curve (in red) compared to the power curve (white) it may become clear. The torque curve reaches its maximum earlier than the power curve which really culminates into a 'peak' in the end. (This is just an example folks, other car's engines might or will definetely look different, of course ...)
If now you want to edit the torque curve in NFSWizard, remember the gradual steps' entries of the tab/the picture.
>>Step one: Understanding the curves' differences
In Carp.txt by default the stepping (when '20' is the highest x-axis entry) is 500rpm, have a look at 'torque curve -> curve editor'
In the picture stepping is identically, but you have to multiply the values by 2 and divide by 1000 since the Carp.txt values are just plain numbers.
For example: Maximum torque (pic) is at 5000rpm, this means: Carp.txt value: multiply by 2 divided by 1000 = 10 (x-axis value)
Too complicated? You'll get used to it. Carp.txt (as said, by default resolution, 20 x-axis values: 1 = 500, 2 = 1000, 3 = 1500rpm and so on)
>>Step two: Transferring a 'real' curve into Carp.txt
It is not necessary to produce a more or less 'clean' curve, even if it looks better, the more important things are the curve's maximum, its slope or 'steepness' and the 'cut-off' rpm.
Now RealTuner becomes somewhat important: According to your edited torque curve (export -> Carp.txt to the car's folder, be sure to 'dublicate' the existing Carp.txt in NFSWizard!) and navigate RealTuner to the desired folder. RealTuner now calculates an Idle rpm as well as a new redline -> save new Carp.txt
Now import the new Carp.txt and you can see a new idling as well as a new redline rpm RealTuner has calculated based upon the new torque curve you had created.
If the redline rpm doesn't correspond to the 'real' data found, alter the 3 or 4 torque values after the maximum torque value in Carp.txt, either lower or raise all values a bit or just lower the cut-off rpm.
<<Remark: if, like in the Countach's case, no redline is given (in the powertrain tab) please read my little tutorial 'Car specification web resources' (or read the additional explanation at the end of this tutorial), it explains how to calculate a redline by certain gear (gearspeed) values>>
Export again, let RealTuner recalculate (You may also notice the gearspeed values changing), save, import and see if the redline has changed to your desired value.
Repeat that again if the result still isn't satisfying, you'll get a feeling for it after several trials.
Same with the idling rpm, raise the torque values a bit (as said, the 3 or 4 values -here- BELOW the max torque value) if idling seems to high, lower it if it may seem to low to you.
>>Step three: entering the gearspeed values from existing specification data
That is, if a somewhat correct redline is being recognized (calculated) by RealTuner, quite easy.
Transfer the maximum gearspeed data ('Speed range') into RealTuner and save it! (pic 'drivetrain')
RealTuner now calculates new 'Velocity to RPM' values, 'automatic' as well as 'manually' shifted in both tabs.
That is very important since now the car knows when to shift gears at which rpm.
You can now transfer the gear values into the gear ratios tab, although NFS cares little about that, since RealTuner by default enters '1.0,1.0,1.0,1.0' .. and so on, same with the final gear entry.
>> Step three (and a half): Calculating the reverse gear 'Velocity to RPM' value
Much more important becomes a small calculation you have to do still for the reverse gear:
By default, RealTuner enters the same 'Velocity to RPM' value for the first as well as the reverse gear.
Start Windows' Calculator and do the following:
.. as you can see in the gear values (as you transferred them into Carp.txt.), either divide the reverse gears' value if it is higher (in most cases) by the first gear value, or vice versa.
Multiply the result (this is your factor) with the first gears' 'Velocity to RPM' value, copy and paste the result into the 'Velocity to RPM' tab, just before the '0.0000' (neutral gear) entry, make sure the minus (-) is STILL before the pasted-in value, otherwise your car will go forward when in reverse gear instead of moving backwards.
>>Step four: 'gear efficiency' tab in NFSWizard ..
Well, that's more or less a matter of personal taste or preferences, but if you entered an appropriate acceleration value (which can also be found in the car's 'full specification' data of the website) in RealTuner (X.XX sec) , I would recommend to leave RealTuner's values unchanged or alter them as said by personal preferences ...
Add.: Explanation: Calculating a redline rpm by certain given gear specification data:
If a car's engine has no given redline (in the 'drivetrain' tab of 'full specification' -> pic 'powertrain') simply divide the 'theoretical top gear speed' of the car's highest gear by the 1000rpm gearspeed value of the same gear, multiply the value by 1000 and you get the approximate redline value.
For example the 1978 Lamborghini Countach LP400 S:
No redline given, top (5th) gearspeed (theoretically): 315 km/h, 1000rpm value (5th gear also): 37 km/h
-> 315/37 = 8.5¯135 x 1000 ~ 8.500 rpm, that's your redline.
Ok that's all so far folks ..