I upgraded from the stock XSE wheel to a 17” wheel and, as you can see on the fitment chart, the new shoes exceed an 8” width with no rubbing issues.
Pulled the trigger and got the TRD Camry rims and put 245x40x19 Dunlap tires on it. They are amazing no modification or spacers needed and the overall height is exactly the same as the stock rims. They are 9.37 inches wide and ride like a sports car.
That looks nice! Got any more pics, like whole profile/side shot? And then just to clarify, the stock Prius 19's are 195/50, did you mean 245/50/19, or are those Dunlaps wider but thinner sidewall?
The middle number in a tire size is a ratio, not a fixed measurement. So a 195/50-19 has basically the same sidewall height as a 245/40-19. 195mm x 0.5 = 97.5mm = 3.84" 245mm x 0.4 = 98.0mm = 3.86"