chain1

Hello all,
I'm contemplating some new wheels for my C/S. Has anyone replaced the stock 19 inch ones? I'm debating between going up to 20s or down to 18s. I want to find a set that will most closely match the diameter of the stock wheels. I'm thinking all black rims would look pretty badass. I love the look of the stock C/S wheels but I can't deal with how narrow they look on the car. My 07's wheels came out flush to the fenders and I really liked that look.
Any thoughts?

908ssp

I think you meant stock tires not "stock wheels" in reference to keeping over all diameter. My suggestion is to go to the web sites of the tires you might be interested in and make a chart of tire sizes that match the diameter that you want. From my study I would say you can probably find both 18s and 20s that fit the bill. Happy hunting.

RAMAIR

I am pretty sure he ment both replacing the stock wheels and tires.

lexustech48

TSW Wheels

High quality stuff man. One of my service managers has them on his IS250. They really make the car look badass!

eightdogsbarkin

Wheel spacers?

Sam I am

If you like the CS wheels, you can always ship them to a custom wheel shop and have them widened.
If you decide to go aftermarket, pick a wheel, and use this calculator to help you find the right diameter tire.

http://www.miata.net/garage/tirecalc.html

Driver72

If you don't like how skinny the tires/wheels look stock you'll probably need to get a wider wheel. The GT/CS wheel is 8.5 inches wide.
You'd be just fine going to 255/40/19 tires on that size which are the size of the Brembo brake equipped tires.

In your OP you seemed to dislike two things:
1. How skinny the tires/wheels look
2. The offset of the wheels not sticking out far enough.

You can go to the 255/40/19 tires for a bit thicker tire and as someone stated above consider a 10 mm spacer to bring the wheels out a bit and more flush with the fender.
If you plan on racing or hardcore driving many (including myself) aren't overly keen on wheel spacers however. It changes the way your suspension and handling geometry work on the car, but so do aftermarket wheels that have different offset from OEM.
But for normal to moderate performance driving wheel spacers pose little issues if you get a good quality spacer.

That would be your cheapest route.

Otherwise look into aftermarket wheels.

I'd go 20 x 9 or 20 x 9.5 if I were you.
18" wheels don't look to great on the Mustang as the wheel wells are large and the 18" wheel looks too small and the tire sidewall then gets too tall.

Here's a good wheel tire calculator for you too:

http://www.1010tires.com/tiresizecalculator.asp

HOTRODD77

What is the offset on the stock rear wheels of a '10 GT? How would a 10" wheel with a +48mm offset look back there? Just wondering if you would get that full 1 1/2" past the stock wheel, or if the wheel will sit further in due to a bigger offset? Whel offsets have always confused me

Driver72

Plenty of 2010/2011 GT owners have 10" wheels in the rear.

When offset is concerned the Cliff notes version of them is:
the lower the number the farther they will stick OUT
so a wheel with an offset of 30 will stick out 10mm further than that exact same wheel with an offset of 40.

Detailed version:
Search Wheel offset there are websites that go into great detail about it and how it's measured from the centerline of the wheel and so forth.

SaddleUp

What's your stock wheels look like? Let's see a picture....