Bought GT500 rims. Tires?

So I bought a set of 4 front base GT500 rims from a 13-14. They all measure 19 x 9.5 with a 44 back spacing. Wondering if I should do a staggered set up or square.

Option 1: I have 255/40/19 all around in decent shape, so I could keep 2 and put 2 new/used 285/35s on the rear. This is pretty much how the 10-12 GT500 is set up. My only concern is 255 seems a little narrow looking on a 9.5 rim. Like on the aforementioned GT500, you can see the lip of the rim on the front wheels in pics.

Option 2: go square with 275/40s all around. This will give me a little less width in the back, but will fit nicely on the front rim. My concern here is that 275 width is too much for the front end as far as steering and spacing and it might tram line more at higher speeds.

What do you guys/gals think?

I should also mention it’s a 2010 GT on boss 302 springs. So about a half inch lower in the front. Wheel image attached(not my car)

I have a set of 285/35 19s, fit without issues on Boss 302 S rear wheels.
I also have a set of 275/40 18s square. No issues.
For daily driving comfort, I like the stock size. But those dont clear the 11&up gt brakes without swapping to the 12.6" brakes.

Yeah I know the 285 will fit in the rear. I’m just concerned that if I go 275 all around, the front might rub at full lock and the wider tires might make the front tram line.

I currently have the 2011 standard GT front brakes-13.25”. No issues with the factory 19 x 8.5 wheels.

The cheaper route I guess would be to just pick up 285s and keep the 255s I have in the front. Just worried they won’t look right on that rim

Juice said:

I have a set of 285/35 19s, fit without issues on Boss 302 S rear wheels.
I also have a set of 275/40 18s square. No issues.
For daily driving comfort, I like the stock size. But those dont clear the 11&up gt brakes without swapping to the 12.6" brakes.

Click to expand...

A 17mm spacer will do the trick in the front.

Like to get some impressions from people with 275/40/19s all around.

I have 285-40-18's on the front of my 2010 GT on 18 x 10 rims, 45mm et (+ a 3mm spacer) and oem 12.6" brakes.

Rears are 305-35-19 on 19x10 rims, (48 mm et).

No tramlining. Fronts don't rub anything at full lock. I'm now lowered 1/2" at the front.... but was lowered 1" at the front for several years, zero issues.

For your application, I would use 275's on all 4 x corners. All the Roush cars came with 275-40-18's (on 18x10 rims). A 285 on a 9.5" wide rim isn't gonna be much wider than a 275 on the same 9.5" wide rim.

I have 275 35 19s on '11-'12 GT500 wheels on my '05 GT with Steeda Sport springs. No rubbing at all. Not sure if the extra height of a 275 40 will cause any issues but I doubt it. A friend of mine has 275 35 20s on 20X9.5 +45 Roush wheels all around on his '14 and also has no issues. Not sure what springs he's on but his car sits at least as low as mine despite the taller tires.

My 2014 TrkPak had Eibach Sportline springs along with the 2014 OE GT500 wheels and the fronts were 44 offset with 265x40's and I'm not sure I could have used 275's with my Sportline springs. The rears were 20x9.5 with a 35 offset and I had 285x35's and I know I could have gone 295's.

Sorry, I meant 50 offset on the rear, not 35.

I have '08 500 on HRE 3 pc 9.5 fr 10.5 rear. Also KR500 Ford racing suspension (tuned for the car), Adj panhard bar and relocation bracket. rear stiffener brace. my .02 is go up one size in the width front. more contact patch, I need the extra meat up front, for the way I drive, better turn-in and braking.
Tire manf are all over the map on actual real sizes.
What's your goal? I have setup many suspensions using math and engineering to fine tune the use of the car.
The KR susp and a 4 wheel thrust alignment using Fords recommended specs.
The best upgrade I have made so far. The KR specs are easy to find. Use a shop with a laser alignment and competent setup tech. predictable 4 wheel drifts out of the apex all day. Your mileage may vary, I drive WFO most of the time. New take-off '13 take off bigger S/C and tune next. pullied down, 67mm T/B, bigger injectors, billet intake and confident 16lbs boost right around 650 T/Q from my tuner. oB

My goal was just to run a wider tire in the back. I’m maxed out as far as width with my factory 19 x 8.5 wheels with 255/40s. It’s more for looks than anything.

These wheels I bought are 19 x 9.5 square, which is great, but leaves me with a conundrum as far as fr/rr tire choices.

Do I just run the 285/35s in the rear and leave the 255/40s up front? This keeps the same diameters I currently have, and even though the tire width on the front doesn’t change, the wider width and different offset of the rim should move it out a little further.

Do I run 275/40s square? This set up would probably be best for handling, and will fill the wheel wells nicely being a taller tire. But it’ll turn my 3.73 rear into something more like a 3:61, and with the 4.6, I need all the low end get-up-and-go I can get. Plus the ride might get a little busy on crappy roads. And I’m not getting as much tire on the back as possible.

Cheapest route would be just getting a pair of 285s since my 255s only have about 19k on them. But I’m still unsure.