i just got my 350z i wanting to put some axis hiro 19-8.5,19-10.5 i have no idea what size tires to buy i come from the domestic side of cars i'm still in the " widest tires possible" mind frame

 

The "standard" upsize is 245/35/19 up front and 275/35/19 in the rear. That size works on 8½/9½, 9½/10½, 9½/10, etc. wheels. Depending on wheel width and offset, minor variations of those sizes will fit without rubbing.

 

another option is 255/35/19 and 285/35/19.
like stated above it depends on your offets for rubbing issues.