This is pretty interesting.
When in 2-player split screen, offline mode, or occasionally in the pre-race menu, you'll see two separate PP values for your car. The value with decimal numbers and (usually) a higher value is the newer PP system, introduced in this game.
The smaller value without decimal numbers is the older PP system, used in GT5, GT6 and seen in the first GT7 trailers. This older system doesn't take tyres or tuning into account, only power, weight and downforce.
I wonder why two different PP numbers remain in the game.
Edit: I've
talked about this before.
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