What's the widest size tires that you can fit on the stock 18" bullitts without having any issues?

I'm just needing tires for the rear wheels.

I've searched and can't find anything.

 

255/45/18 is the biggest recommended size although there are a few people that have pushed the envelope and gone 275's.

 

Do 255's.

 

Indeed, anecdotal evidence is a poor substitute for reccomendations based on proven engineering.

 

Try this calculator and you'll get a better idea on what works best.

http://www.bigcustomwheels.com/rt_specs.jsp

 

I did the calculator thing and the closest matches that I could find (i.e. larger tires that will fit w/o any mods and that will stay within 2 mph of speedo) were 255/45/18 (which, while wider, are actually a fraction shorter than stock and would leave an even bigger gap in the wheel wells) and 245/50/18 (wider and a tad taller but still easily within tolerances -- but an oddball size that's hard to find).
Everything else was either too tall, too short or too wide. Of course I was trying to be somewhat practical.
There you have it.

 

I played with that thing for days before I made my decision and went 275/40/18 x 9.5 on all 4 corners. I got the bigger wheel gap, but I lowered it and now it's all good.

Were you going to drop it as well?

 

You should be able to do 275s, depending on the tire manufacturer. Remember, different manufacturers will have different actual sizes- for example, my M&H racemasters are 325/45 and their section width is almost the same as my Nitto #555 275/40s.

 

+1 Don't go beyond 255/45/18 with the stockers.
Of course if you don't intend to ever corner hard or drive over 55, you can get away with whatever you want.