Most Aggressive 513M Setup That is Achievable & Liveable

[512systems]

Thanks for looking guys. I am swapping from 437's to a set of 513's currently and want to know the most aggressive setup I can get away with. I am running 265/285 35/19 Cup 2's on the 437's. The car is never tracked but driven hard in the canyons. I have nailed down that I want to go with PS4S's because there isn't a Cup 2 size that works. Am I able to get away with 265/285 35/18 and/or is that a good idea? There isn't a 285/40 available it seems so I could do 265/40 and 285/35 however I don't know what is best obviously. I have scoured the forums and haven't found the answers so any advice is hugely appreciated. I am open to spacers on stock width 255/275 if that's a better option. Basically I am looking for the widest contact patch and best transaction for those 18's. Thanks so much!

[gatorfast]

If you wanted to try the continental extreme contact sport tires there is a 285/40/18 available for the rear which is what I run.