You don't want 19's for an autoX/road course wheel. You want 18's. The tires are a lot less money and there is a bigger selection.
You can fit 315's all the way around with some work. The more popular setup is 18x10's with 285's or 295's on them.
Here is something I wrote up about offset/fitment:
There is a lot of confusion on how wheel offsets work, what wheels will fit, etc. I’m going to skip the tutorial on how wheel offset works and go straight to what offsets work with what width rims. This is not because I don’t think you should understand offset, it’s because I don’t feel like typing all of that. I recommend doing a google search on wheel offset and getting yourself familiar with how it works so you can figure this stuff out in the future.
I would also like to add that I don’t consider wheels/tires that stick out past the fenders or are even with the fenders right…..because they are NOT! Yeah, tires/wheels that are flush mounted with the fenders look cool, but there are WRONG. During semi hard cornering they will rub, period. And if they can rub, they are wrong. There is no excuse to have tires that can contact the fenders. You can run 315’s at all four corners with no rubbing if the wheel is offset correctly. Having 275-295’s that can rub, there is no excuse for.
There are a TON of “Mustang” rims out there that don’t fit! Do not just blindly take a manufacturers/vendors claims at face value. Research the fitment yourself and make sure you are getting rims/tires that fit correctly.
Here are the popular wheel widths and the offset range you want to run them in to fit CORRECTLY. Wheel diameter doesn’t matter:
There is a little more leeway with the front because the wheel/tire is tipped in at the top (camber) which allows the use of a wider rim w/ less offset than if they were perfectly straight up and down. Push these minimum offset numbers (the smaller of the two) at your own risk. Cars with 2.5deg+ of camber will be a lot more forgiving than cars running the stock 1-1.5deg of camber.
9.0” rim 33-38mm offset
9.5” rim 39-44mm offset
10” rim 44-50mm offset
10.5” rim 50-53mm offset
9.0” rim 35-38mm offset
9.5” rim 41-44mm offset
10” rim 48-51mm offset
10.5” rim 55-58mm offset
11” rim 62-63mm offset
Waiting on 2019 GT500 2012 GT Vert Brembo - Stock-ish 2012 F-150 FX4 EcoBoost 4x4 406rwhp/522rwtq. The most powerful EB F-150 on the planet?
2007 GT-TSR/Stops/Turns/Custom Everything/3.4L Whipple Crusher/1000hp SOLD