Tires and rear end?

[pontiacregal]

I was wondering what is the largest slick I could mount in the rear? Also what rim backspacing w/ stock rear-end. I was also thinking of going to a 9-inch rear end. If I go with a 9 inch is there a better length than stock to use. Should I notch the frame rails?

 

[Grumpy]

depends how big of a tire ya want in there ... 275/60/15 MT drag radials fit pretty good with no mod's .. can get a bigger tire if ya want the rear end high in the air

 

[Boost231]

not sure what rim or back spacing my buddy is running but hes running 28X12.5X15 on this car. only thing he did was trim the fender lip