I decided to run more testing this evening to back up the data. First some more laps tests;
Motegi Speedway lap times.
Pick a car, punch in three consecutive laps and take the average times. Please note I de-tuned the 787B with the lower grip tyres. The purpose of the test is to check consistency, not outright speed.
Two very different cars obviously but the results were still surprising. Whatever physics bug is causing this discrepancy seems to manifest itself in different ways. It's possible that grip may be reduced, but in some cases improves balance which keeps lap times equal. But under no circumstances does the post-pit tyre set improve laps times.
Next up - Accelerated tyre wear test
Standard Escudo Pikes Peak - SSRX
2 laps with pit stop.
Full wet weather tyres
Fast tyre/fuel depletion
At the end of the first lap the tyres on all three cars had barley done any work. Only the highly tuned Supra showed slight wear on the left rear while the fronts cooled over the run. Which is slightly bemusing given it maintained an average speed of 450km/h. Obviously the tyre physics are only heating up due to corner scrub.
After the pit stop the Supra had worn both rear tyres down to 7 before the first bank. It didn't even make it to the second banked turn as the tyres wore to 1 and 2 respectively, sending it into a massive spin on the straight. The front tyres didn't seem to be affected at all but the rear (driving) wheels were getting torched.
So I decided to switch to the 4WD Escudo. Once again lap 1 showed virtually no tyre wear and the rubber remained cold. After the pitstop all four tyres started to wear noticeably, although the rears were a little worse.
Then I tuned up (power wise anyway) a Focus ST. Again, all fours tyres not worn after lap 1 and remained cold. After the pitstop the rears didn't suffer, but the front driving wheels showed significant wear.
In all cases above I noticed the following:
Constant tyre screeching in a straight line
I know many already are aware of this, but if you want to replicate it for yourself then throw a set of full wets on during a pitstop. It happens with all the tyre types, but the full wets give the loudest screech.
Car shakes violently after pitstop
The game tries to replicate cockpit movement somewhat anyway, but after a pitstop this shake becomes much more violent. The horizon becomes something of a blur because the camera is shaking so much.
Finally - The ratio test
Tests were run on SSRX before and after pit stop.
Measurements were done by capturing the recorded replays and frame advancing the footage until the tacho needle hit 8000rpm.
The race and wet weather tyres are broken. Also seems each tyre increases in diameter as the compounds get softer. No idea why that is, but the purpose of this exercise is to check consistency between the first set of rubber and the set fitted during the pit stop.
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Seems like the game is referencing one set of default values when you enter the track (values for tyre compound, diameter etc) and another (screwed up set of erroneous data) when performing a pit stop. Whenever you go to track the tyre values seem correct lobby (but leave your car entered or 'on track'), when you go back to the car the tyre values are correct again and the bug is gone.
Whatever values are referenced during a pit stop scenario must be screwed. We know for a fact that the tyre circumferences are wrong for the racing & wet tyres and something is 100% getting screwed in the physics department at least with the driving tyres. Theres no questioning the results of the speed and tyre wears tests. All can be easily replicated by anybody.