[Ed M.]

Hi Guys, I was wondering if you could help me out. I recently ordered a new 2007 Mustang GT and it will be arriving in a few weeks. One of the first things I'm going to do is change out the factory wheels and replace them with a set of 19-inch or 20-inch wheels and a new set of Goodyears all the way around. I've been Googling the net for information on tire widths and general wheel specifications etc., but have been getting a lot of mixed information, so I decided to try here.*

What I'd like to know is when ordering a set of wheels, what is the preferred (or optimal) offset for the '07 Mustangs? I've heard somewhere between 30mm and 45mm, but was hoping for something a little more specific. And would that offset be "positive" or "negative" offset for these '07 cars?

The next question is (you guessed it).... What's the widest tires that I can squeeze under the rear fenders WITHOUT and suspension or fender mods. In other words, since I'm not looking to do any modifications to the fenders or the suspension (at this time), what's the widest tire that will fit the factory setup? I want to avoid ANY rub... I don't want the slightest rub or scraping at all. I've heard that people have been going all the way up to 315's in the rear with 20-inch wheels without any problems at all. I know that a seemingly factory/stock Shelby I looked at recently had 285's in the rear, and the one I saw at a local "cruise night" here in NJ had 305's in the rear and 275's in the front of his 2006 Shelby. Going with 285's, or even wider would be pretty sweet looking if it's possible. The "deep dish" style would definitely give the car a much more "aggressive" look. *

I checked out some wheels that Mustangtuning.com was offering just to get an idea, and I don't plan on going with that particular style, but the "deep lip" effect is something I'd like to achieve with my car. I just want to do it right and not make any stupid mistakes.* Same goes for the front tires...

*I'd like to go with the widest tires possible in the front as well. Again, the widest that will fit the stock factory setup (for now). This is where it gets a little tricky because I've heard that If you go with any width above 255's in the front the car will track and steer awkwardly. This would be unacceptable and probably dangerous! Of course, this could all be nothing to to worry about - we'll see. In any event, during my internet searches I read of people claiming to have put 275's on 20" wheels on the front of 2005+ Mustangs!*Thoughts? Suggestions?

It also might be worth mentioning that I eventually plan on lowering the car and adding all the appropriate suspension parts in the future. In the mean while I'm gathering as much information as I can. In particular, I'm searching for spot-on specifications for the optimal offset and maximum front and rear tire widths for both factory as well as for modified setups (i.e. a car that's been lowered). It would be interesting to know the differences and limits for both setups.*

I like the deep dish/low profile look. The specs. I jotted down from a stock 2006 Shelby I seen while at a local cruise night was as follows:

305/25/20's on the rear.*
275/30/20's on the front.

I'm also curious about how these tire and wheel combos will affect overall ride quality.

Thanks in advance for any information and suggestions you can provide!

--
Ed

[whatisee]

20" Deep Dish Bullits look REALLY nice

[Beachhat2]

have you made the tire and wheel mods yet?

[Phoenix Scanner]

I know people who have done 265 front and 315 in the rear with no problems. It all becomes a matter of the perfect offset when you push the limits. You really need to take some careful measurements to determine the correct offset.

With stock suspension, I have had a few people tell me they really get hammered on 20's over rough roads. Also, it is worth noting you will reduce your rear wheel horsepower, slow your acceleration, increase your braking distances, and there will be an effect on turn in at speed, if you choose 20's, and even if there are only small changes with these things, they are there. With greater unsprung weight, also comes other issues when cornering on rough surfaces also. Of couse, with an investment in suspension mods, most of these things can be dealt with to various degrees, and if you spring for forged wheels, the weight can be kept to near stock levels as well.

If the looks are worth it to you, just take some careful measurements and enjoy! I do think 20's look awesome.