well, i got 7" wide wheels, and my 195/50/r15 p5000s fit on, but i wouldnt reccomend (neither do the manufacturers) going too wide as it kida defeats what the side walls of the tyres were designed to do. If you put them on say a 8" wide wheels instead of the 6" there designed to go on. The angle of the sidewall to the vertical, is greater. This means that the sidewall which was meant to work at say 15 degrees is now working at 25-30 deg. The tyre will wont work as designed and you will destroy the sidewalls as they flex and actually wear against the road. Meaning less miles per tyre and impared handling!