I recently put on a staggered set of track pack wheels on my 2013 3.7 and went with 245/45R19 in the front and 275/40R19 in the rear but I would like to go wider when I replace these tires. What I'm wondering is how wide I should go? The fronts are 19x9.5 and rears are 19x10. I was considering 265 in front and 295 in the rear?

 

265/295 would be a good combo. What tires are you looking at, and what wheels do you have?

 

They are the track pack wheels, front two are originals from a GT and the backs are reproductions from oewheels so I could get 19x10
I'm leaning toward the new firestone firehawk indy 500's. I suppose I should mention I've already lowered it about 2" but it doesn't look like clearance will be an issue

 

If those are the Brembo wheels they are 19"x9". A 255 is the "best" fit, although you can get a 275 on it.
I've run 295s on 10" wheels with great results. 305 will fit too

 

I disagree on the 255s on 9s. Ford used 275/40/17s on the Cobras before, but I think 265s are the sweet spot for the 19x9s. I'm currently running the stock size up front and 275/40 on the rear of my Brembo wheels. Prior to that I had 265/40s on the rear and I think they fit perfectly. Ford should've done 265/40 all around, but they're a much less common size than 255/40.