The PI system in Forza has been troublesome for most of the series. Given this is supposed to be a ‘built from the ground up’ reboot, I believe it’s high time this system was overhauled to make it better at balance. As a resent example:
The small amount I have been playing recently, I’ve been tuning various cars for classes (a complete chore with carPG, but that’s a different issue). I decided to take the BMW 323ti from D to C class as a grip car, you don’t see many of these imho. Now, as horrific as it was stock, once I’d actually tunned it properly, I managed to get something not too shabby out of it. It actually felt good to drive and grippy. Once I’d finished, I decided to check it at rivals.
It’s 2~3 seconds off the civic’s/mx5’s. Sure, I’m not top tier as a driver (Most forza’s I can edge into top 200, sometimes better), but the Mx5 was far faster out of corners.
Now, my point is, when you take the 90 mx5 (currently first on leaderboards), it’s running 188hp. When I build it for grip around this power, I get a car that, according to the PI system, is close to parity with my BMW.
BMW:
Handling - 3.9
Braking - 3.9
Accel - 2.9
Speed - 1.3
Mx5:
Handling ~ 4.0
Breaking ~ 3.7
Accel ~ 3.1
Speed ~ 1.1
These cars should be close, but they’re no where near. The BMW weighs ~2300 lbs, the MX5 is something like ~1800 with almost the same power. That’s ridiculous. It has ~20% advantage in power to weight but a comparably close accel PI stat, which is an outright lie. The accel stat is seemingly unaffected by actual power/weight. It actually seems to mainly go off stock gear ratios, making it way off when the ratio’s are properly tuned. This held true I believe for the older games too iirc. Turn10, you’re clearly tracking the power to weight metric, it’s even a tracked stat in the car info pages. You really need to consider reworking the PI system, it just doesn’t work for balance.
As an idea, perhaps make the metrics *simple, track max possible lateral grip, speed, power to weight and ignore the stock settings effects on these numbers whenever a tunable part that effects these is installed. Instead, base the PI at that point on the maximum potental. Good tunes would be the ones that get as close as possible to these maximums at that point. Otherwise I guess, you would have to have all tuning settings directly effect the PI.
Still, regardless of how it should be fixed, I think it’s high time it was updated. Like most of these games, it’s been the same content and systems for decades, it’s beyond late for some actual advancement of the formula of forza.