Maximal car power and driver performance?

Hello guys,

I just wanted to try out if I can reach 500 kph in GP4. Unfortunately, somewhere at a car power of 1782 in the performance file, the AI cars are only driving backwards at the start and crashing. Only four or five cars are running normal and reaching top speeds up to 492 kph, but I want to see the 500 kph. Is there any possibility to fix that bug? I also remember that sometimes single AI cars start to ride backwards in the direction of traffic up to 480 kph and then crashing at the next corner to never get back to the track again.

Also I'm wondering what value is the best possible driver performance. I don't realize any great difference at values above 40000. Even at 200000 the AI cars are crashing quite often. Has anyone an idea if there is a way to avoid that?

And at last I wonder if it's someway possible to get the human player's car quite equal with the AI cars when changing some settings. My record is 454 kph at Reims, the record of AI cars is 484 kph in Hockenheim 1968, with slipstream even 494 kph as I remember. There are also massive upshift problems for the human player's car with car powers more then 1700. The gears from 3 to 7 are upshifted extremly fast behind each other. That's also very weird and not really senseful.

Any suggestions are welcome. Thanks!

Your TGF1DRIVER

The game uses fixed point calculations for most stuff. The result is that many parameters have a maximum, and will become negative beyond it. E.g. if there is a 16-bit internal value and it reaches 32767, then if you increase it more it becomes -32768, -32767, etc. The default power value is 16384 internally. It will overflow to -32768 if you double it, making the car drive backwards. A value of 40000 is probably interpreted as -25536, and 200000 as 3392.

So the game simply has limits you cannot go beyond.

René Smit, Independent Software Developer.
Download my GPx tools here.

Hello Rene! Thank you for your answer. I will try out more different settings soon. But there's just another strange thing I want to report to you: When I'm using a car power of 1782, in Hockenheim 1968 (slot 12) there are between 3 and 8 different cars which are driving quite normally. When I'm starting another race there are maybe more or less cars driving normal than in the race before, but it's not the same cars as before. That's really strange. And when I'm using the same performance file in Reims-Gueux (slot 15) the are every 22 cars driving backwards at every race and no car is driving normal. But sometimes 1 to 5 cars are driving slowly in the grass next to the track with about 80 kph. I think that might be caused by the driver's power variability, so I will try this with a driver variability of 0 right now. Well Rene, can you advise me some performance file settings which might be the one for the fastest possible cars? Thank you.

That's not strange because the power is randomized (reduced by a small random amount).

If you want to make the cars faster perhaps you can play with the physics editor?

Maybe you can also reduce the air resistance.

René Smit, Independent Software Developer.
Download my GPx tools here.



Edited 1 time(s). Last edit at 05/19/2019 09:46PM by SDI.

Well, I haven't used physics editor yet. I tested some other settings and got the AI cars never faster than 492 kph, that seems to be the top speed limit in GP4. For the player's car I will try to reach more than 454 kph, my personal record. This might last the whole rest of the evening....

For the internal speed value 492 kph is not the maximum. The theoretical maximum is more like 561 kph (32767 * 0.3048 * 3.6 / 64).

René Smit, Independent Software Developer.
Download my GPx tools here.

Very interesting! Now I found out that 3513 is the maximum car power for the player's car, at 3514 the engine is dead. With 3600 I'll have a very slowly car. At 3530 and 3520 strange things are happening, such as the player's car is invisible or is shown twice and another car is missing. I think that's a bug that really doesn't matter for playing the game. When using 3513 as car power and 32768 as driver power I'm reaching a maximum top speed of 454 kph without slipstream and 461 kph in the slipstream in Reims. I think 461 kph is also the theoretical maximum, do you have a calculation for this value?

In Hockenheim 1968 there is also 461 kph the maximum. Faster you cannot drive in GP4 as a human player.

See here: [www.youtube.com]

Mods & Tracks for GP4 - [www.mediafire.com]

Keeping alive the GP4

Meteoro405 schrieb:
-------------------------------------------------------
> See here:
> [www.youtube.com]

How did you do that!?

And by the way: Buenos Aires 1979 is faster than Reims!?

See? I predicted the correct moment of overflow

René Smit, Independent Software Developer.
Download my GPx tools here.

Is only graphical example of your words

Mods & Tracks for GP4 - [www.mediafire.com]

Keeping alive the GP4

I wanna know how I can get to this overflow too! Is it only possible on this track?

I remember that years ago while I played with Physics editor I was able to easily reach 561 kph and after start to fly, as in the video.
Now I discover the true reason for this happening, thank you Renè!

Probably I only changed the maximum power (maybe to 50000 or 65000? I don't know at which value the overflow occurs). With automatic gears, car was unable to shift after 1st gear, but it wasn't a problem except for the unreal sound (but overall... all the rest was also unreal!).
I think that at so high power the result is not dependent on the track, given a sufficient long straight to accelerate.

@ TGF1Driver2: the result is not dependent on the track.

@ Jarno_Trulli: In my physics experiment, the gears change from 1 to 7 in a normal way, the same as sound.


If you want, I can search them on a DVD and upload them

Mods & Tracks for GP4 - [www.mediafire.com]

Keeping alive the GP4