I'm using a 255/35/18 on the front and it's almost the exact height as stock. I've used a 245 as well and it's 1/4" shorter more or less. You'll need a spacer to clear the upper suspension bolt. A 235 on the stock rim only has 2 mm clearance to that bolt and a 245 is 5 mm wider on the inside. I used a 10 mm spacer. The rear is fine. So if you have the spacers and longer lugs go for it. If not, you'll have to add the cost to the bargain, and that price is a bargain for PZeros. As long as the difference from front to rear doesn't vary more than 4%, more or less, from stock the computers won't mind.

Les