What's the widest wheel I can fit without camber?

I’m looking at some wheels that are 15x8.5 are they too wide?

It’s not width that’s the largest factor, but more so offset.
Also, some negative camber is better than none in terms of performance. Also, how low is your car? That’s also something to be considered. If you run that wheel without lowering your car, sure it will fit but will more then likely stick out past the fenders depending on the offset the wheels have. Most wheels with low offset on Hondas need a lot of negative camber to fit, rolled/pulled fenders, so on and so forth. So in short answer yes the wheels will fit, but probably nor how you want them to unless they have a higher positive offset. I think the widest wheel would probably be a 7 inch wheel I’m not entirely sure

I run a 17x9 +40 CCW Classic, with 225/45/17 Falken Azenis…which is a super meaty setup. You can run a big and wide wheel on DA’s, just not super low offset. I’m on stock upper arms, running natural front camber. Set up at a track height, so about a finger gap on each corner.

Note, when rolling you will notice the rears will only roll so far, as they like to hold their shape!

This is a pretty nice tool for getting a rough idea of what different widths/offsets will look like:

http://www.wheel-size.com/calc/