Forza Motorsport PI explained: What is Performance Index?

Each car in Forza Motorsport is rated by multiple different parameters, and while some are straightforward, things like PI (Performance Index) can be difficult to understand. Here’s what it is and how it works. 

Every time you pick or buy a car, Forza Motorsport will throw in some numbers to help you better understand how it’ll fare against the best of cars and tracks. Some of them are easy to pick up, like Speed and Handling, but others, like PI remain a little unclear.  

PI has been a standard grading system across all Forza Motorsport games since 2, including Forza Horizon, and how it is graded this time also remains largely the same as seen in past entries. 

So, what exactly is PI in Forza Motorsport? 

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What is Performance Index in Forza Motorsport?

Performance Index or PI, is a metric that indicates the overall performance of the vehicle. To determine an individual car’s PI, the developer pits that particular car in a virtual lap test, and the better it performs, the higher the rating it gets. 

PI determines which class a car will be in: E, D, C, B, A, S, R, P,  and X. Here’s the PI rating for each class in Forza Motorsport: 

• Class E: 0–300 PI
• Class D: 301–400 PI
• Class C: 401-500 PI
• Class B: 501-600 PI
• Class A: 601-700 PI
• Class S: 701-800 PI
• Class R: 801-900 PI
• Class P: 901-998 PI
• Class X: 999 PI

PI does not, however, mean a particular car is better than another, as PI is a single assessment of the car’s lap time. Because of how dynamic each track and situation is, a lot of the time, lower PI cars can outperform higher PI cars. Upgrading a car will change the PI but there is a cap to how much you can upgrade a particular car.

So, in a nutshell, a PI will draw a ballpark on how a car can perform in a general situation. It is directly related to the car’s handling, brake, speed, and acceleration stats, as a car that has good 9.0 or 7.0 ratings, will have a higher PI, as it will perform better.

That’s all you need to know about PI in Forza Motorsport for more on the game check out:

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