Ferrari

I originally posted that I was getting 18's, but decided to go with the 19's because the 18's don't look that much different than 17's.
However I don't want to lower the car, which some people say that I must do, don't know why, but anyway...

My cousin said that I don't have to lower the car and that I should use 245 / 40 ZR19 (f) and 265 / 35 ZR19 (r), but I don't know if thats right, so I had to ask the pros, you guys!!

Will this rub and what is the difference between Z rated tires and Y rated tires?

Sorry for all the questions guys but I am not to familiar with this department!