Changing power values of unofficial cars

[TheMaroon47]

So I have a question for any modders out there. I understand that changing the RPM and torque values within the power.lut file increases/decreases power accordingly. However, torque and horsepower are different things and depend on engines. Example: With the GT500 cars mod I found for AC, the cars are producing around 493hp and about 630nm of torque. Now, taking an example in real life, i.e. the GT500 Nismo GT-R, which produces about 650hp and 700nm of torque, I just can't see a way of balancing the values. In the case of the GT500 cars mod, the cars actually accelerate slower and have a lower top speed than the GT3 cars already in AC (while in real life the GT500 cars would blast past). Any help would be appreciated.

 

[Stereo]

Horsepower is just the product of torque & rpm (in imperial it's 1 hp = 1 ft-lb at 5252 rpm) so a table of torque vs. rpm explicitly contains horsepower as well.

If a mod doesn't have enough horsepower just change the rpm but leave torque alone.

 

[TheMaroon47]

Horsepower is just the product of torque & rpm (in imperial it's 1 hp = 1 ft-lb at 5252 rpm) so a table of torque vs. rpm explicitly contains horsepower as well.

If a mod doesn't have enough horsepower just change the rpm but leave torque alone.

Ah, but I don't exactly have the specifics on the RPM/Torque values. Another thing I noticed is that changing values in the power.lut file does not change the values seen in the car specifications in AC.

 

[Stereo]

Yeah, the UI files in the car preview have no physical effects, they're just drawn in the ui. Only the power.lut file is used physically.

 

[TheMaroon47]

Yeah, the UI files in the car preview have no physical effects, they're just drawn in the ui. Only the power.lut file is used physically.

Well I'll see what I can do in the meantime. Thanks for the help. Also, absolute noob here in modding as I'm sure you can tell.

 

[Neilski]

Horsepower is just the product of torque & rpm (in imperial it's 1 hp = 1 ft-lb at 5252 rpm) so a table of torque vs. rpm explicitly contains horsepower as well.

If a mod doesn't have enough horsepower just change the rpm but leave torque alone.

I agree with all of that, but adding more rpm won't help to boost the power if the torque has already plummeted (if I understand your suggestion correctly - to increase the rpm limit?).

Remark for @TheMaroon47 - when you see engine power and torque values stated as just a single number for each (e.g. 123 bhp, 456 ft-lbs) it can be very misleading. Cars with very peaky power curves (depending on gearing!) can be slower than cars with much less peak power but a flatter curve...

 

[TheMaroon47]

I agree with all of that, but adding more rpm won't help to boost the power if the torque has already plummeted (if I understand your suggestion correctly - to increase the rpm limit?).

Remark for @TheMaroon47 - when you see engine power and torque values stated as just a single number for each (e.g. 123 bhp, 456 ft-lbs) it can be very misleading. Cars with very peaky power curves (depending on gearing!) can be slower than cars with much less peak power but a flatter curve...

Yes I understand it now. It was quite confusing to work out at the beginning. However, as I mentioned, the power and torque curves are not accurate in the first place, so some tweaking will need to happen in the coming days. As I understand it, his suggestion was to assign lower RPMs to the torque values. Since both of them need to be tweaked, I'll need to try a few different things. Besides, fiddling is part of modding.
PS: I might post the mod once I finish with the power values. Should be noted that I didn't create this mod, but I can't for the life of me find the author of it. As far as I have found out, it was posted in 2015 with another identical post in September of this year. Since it isn't on Race Department, I feel that it should be posted.

 

[Neilski]

As I understand it, his suggestion was to assign lower RPMs to the torque values.

Ahhh, OK, that makes much more sense

Btw, when you say the curves aren't accurate, you mean they don't match the real car, or that the UI curves don't match the power.lut used in-game? (I must have a go at car mods myself one of these days...)

 

[TheMaroon47]

Ahhh, OK, that makes much more sense

Btw, when you say the curves aren't accurate, you mean they don't match the real car, or that the UI curves don't match the power.lut used in-game? (I must have a go at car mods myself one of these days...)

In the sense that they don't match with the real car. I believe this mod was created in 2015 with some anonymous updates to keep the liveries up to date. The power curves are fine for the current configuration. The problem is that manufacturers like Nissan are so secretive regarding the specifications of the car that there is basically no information to go on. Thus, to get an accurate gauge on how much power/torque the cars have, I'll have to watch the SuperGT season all over again, which when including the Suzuka 1000km, will take up at least the next 2 days of my life. It'll be good fun for sure.

 

[mclarenf1papa]

I agree with all of that, but adding more rpm won't help to boost the power if the torque has already plummeted (if I understand your suggestion correctly - to increase the rpm limit?).

Remark for @TheMaroon47 - when you see engine power and torque values stated as just a single number for each (e.g. 123 bhp, 456 ft-lbs) it can be very misleading. Cars with very peaky power curves (depending on gearing!) can be slower than cars with much less peak power but a flatter curve...

It depends on your definition of slower...provided the same gear ratios, a peaky engine might be slower accelerating, yes, but assuming all else is the same, a car with more power will have a higher top speed.

 

[Neilski]

It depends on your definition of slower...provided the same gear ratios, a peaky engine might be slower accelerating, yes, but assuming all else is the same, a car with more power will have a higher top speed.

Very good point! As you probly figured out, I was only considering lap time. Even that will depend on the track...

 

[Joseph Maxx]

Since it isn't on Race Department, I feel that it should be posted.

Just a quick note, forum rules are if you don't have the original creators permission to post it then it can't be posted here. Also, any content that has been ripped from another title is also not allowed here.

 

[TheMaroon47]

Just a quick note, forum rules are if you don't have the original creators permission to post it then it can't be posted here. Also, any content that has been ripped from another title is also not allowed here.

It seems that the creator has disappeared off the face of the planet. Or something close to it anyway.

 

[TheMaroon47]

Update: So I've gotten a little closer to the supposed power values/acceleration of the cars. However, are there any guides on this forum for modding turbos? I can't seem to find any. I'm currently 70Nm past the supposed torque curve and >100bhp down on power.

 

[Neilski]

Have you tried monitoring the boost pressure? (With the dev apps for example.) The game uses (1+boostbars)*torquefromlut to calculate the live torque.
You can't get torque right and power wrong; they are linked by speed.

 

[TheMaroon47]

Have you tried monitoring the boost pressure? (With the dev apps for example.) The game uses (1+boostbars)*torquefromlut to calculate the live torque.
You can't get torque right and power wrong; they are linked by speed.

I'm talking about adding turbos and how to do it since the cars themselves don't seem to come with them, though the real ones do.

 

[TheMaroon47]

Right, so I've gotten the car to roughly where the power and torque levels should be. The problem now is that having a 650bhp+ and 700nm+ power.lut compared to the original 493bhp and 550nm power.lut has umm... made the car pretty much undrivable. Any of you gents know how I could edit the drag coefficients?

 

[kprimo12]

anything ever come of this ?