October 8, 2020
How to Manage the Performance Index Rating in Project CARS 3
Performance Index Rating (PIR) is a physics-based representation of how well your vehicle should perform against other vehicles.
Several factors are combined to create the PIR for every car (and can be altered with upgrades and downgrades):
- Top speed (based on power/drag)
- Acceleration capability (based on grip, weight, weight distribution, CoG height, and drive type—2WD/4WD/RWD)
- Cornering capability (based on grip, aerodynamics, and weight)
- Braking capability
These are then calibrated against reference laptimes for all vehicles.
Because this data has been calibrated against hundreds of reference laps with a wide variety of vehicles, it can then be used to show you what kind of impact upgrades will have on the performance of your vehicle.
Because the final PIR value combines multiple physics characteristics, two different vehicles can have the same PIR. For example, a low grip, powerful car could have an identical PIR as a low powered, high grip car. Which of these would come out on top in a race would then depend on both the track—and, naturally, the driver.
So, if your car has a high PIR due to remarkable handling, but isn’t massively powerful, it will perform better on a twisty circuit versus a similar PIR vehicle with dollops of power.
Some upgrades therefore have a bigger impact on the PIR rating than others. For example, tyre upgrades can make a big difference, particularly if your vehicle is struggling for grip.
Also, because the PIR rating considers “useable grip”, throwing all the power at a vehicle might not increase the rating as much as you might think.
If you want to drop a class with your favourite car, you will sometimes need to shed an upgrade or two. This is achievable in the same way that you upgrade cars in-game. In other words, if you already have a part and you want to equip it, it costs 50 credits, and it will cost you the same to downgrade to your default part, or if you then decide to ‘re-upgrade’ to your better part.
Important to note, however, that the only “upgrade”’ that cannot be removed is the race conversion upgrade—that is permanent and can’t be undone, so think carefully before committing to this final step.