No 18 inch wheel eveyone e-mail ford and scream

[jmuva44]

Another bad note on the 18" wheels is that tires last half as long and cost twice as much. Those tires, because the sidewalls are stiffer, use the tread up more to create traction. Not only that, but 18" tires typically but not always, have lower tire wear ratings (stickier tires) because they typically go on higher performance cars. I had 18" wheels and got rid of them cuz I was going through those expensive tires way too quickly. A 17" wheel with a moderate side wall is more for me. I get decent looks, good ridability, and more reasonable tire wear on a much less expesive tire.

I just dont know if they feel there would be a big enough of a demand for a high dollar wheel on a fairly inexpensive sports car when compared to the Viper, BMW and Corvette where the customers typically have more disposable income. Mass producing an 18" wheel and creating a stock of 18" tires is not something that is cheap.

 

[hersheyman]

The new mustang will be offered with 18" rims a year after lauch (or possibly earlier) with a set of 255 45R18 tires.

This has been confirmed numourous times and even in a video of the pony drive (announcer introducing the mustang confirms it).

Can you give me a website or something to confirm this about the 18" wheel option next year? I have been speaking with a sales manager at a Ford dealership and he has not heard of that option yet.

 

[Magius231]

exactly, you're talking about rotational intertia. you can get the rotational inertia of any rotating object by looking at every little bit of mass and its distance from the axis of rotation, so basically its a calculus calculation. For a hollow cylinder, I=MR^2, for a solid cylinder its 1/2*MR^2, probably the best approximation for a wheel is the hollow cylinder, since most of the mass is at the rim right? anyways, it doesn't matter cause the 1/2 is just a constant factor that cancels out if your comparing two situations.
You prolly all know F=ma, force equals mass times acceleration. Well its pretty much the same with rotation, torque equals rotational inertia times rotational acceleration. Or rotational accel = torque/inertia. If you increase the radius of the rim from 17 to 18, a factor of 1.06, you increase the inertia by a factor of 1.12 since the inertia is proportional to the square of the radius. That means you decrease your acceleration by a factor of 1.12, since the rotational acceleration is inversely proportional to the inertia. And since the linear acceleration of your car is directly related to the rotational acceleration of your wheels, if you were hittin 60 in five seconds, its gonna take you 5.6 seconds now.
Of course this is an oversimplification, but it gives you an idea of how big a role the radius of your wheels plays in straight line acceleration.

thats all well and good but you aren't taking the tire into consideration. If the tires are the same overall height, the increased mass from the rim will be offset somewhat by the decreased mass of the heavy ass rubber tire on the end of it.

I don't know anyone that has lost .6 in their 0-60 time from switching to one inch taller rims...

 

[slashmatt]

Another point...

The Mustang GT is NOT an expensive car by any stretch of the imagination. You could buy two and still not pay for a loaded C6 COUPE! I'm just saying, 18" rims generally don't come, even as options, on cars below $30k. When, and if, the Cobra comes out, I wouldn't be too suprised to find 18's or even 19's. Until then, I wouldn't expect much more than that. The only expensive thing about a Mustang GT is the insurance, and that's just the way Ford wants it.

 

[Mr_dcj2001]

But we're talking about a MUSTANG, not a sports car.

So what category would you put the Mustang in?

 

[Mr Black]

Just to let you guys know, in that little estimation i did about the effect of larger rims on acceleration, i made a big mistake. That kind of a difference in acceleration would be observed if the mass of the car was negligible. Like say the work required to linearly accelerate the car as a whole was nothing compared to the work required to accelerate the spinning of the wheels. So if you were comparing two super lightweight chassis with super lightweight engines, one with 17' wheels and the other with 18', then you'd see something close to that difference in 0-60 times. It wouldn't be too hard to actually figure out the difference for real car though. I'll do it some time later though, i'll post again when i've figured it out.

I was just going to make this point but you beat me to it The extra rotational inertia will make a difference, just not the entire difference. Exactly how much is a math issue and I'm way too tired and lazy to do the calculations.

 

[65conv50]

So what category would you put the Mustang in?

A Mustang is "Sports Coupe" or maybe a GT car, depending on equipment and setup. Ford actually broke new ground when they introduced the Mustang, so much so that a new term was coined: "Ponycar". I personally think that is more accurate. But sports car? No.

A sports car is quite different. (The following may have exceptions in any one category, but not all). A sports car has only 2 seats. It is small, much smaller than a Mustang. It is designed for close interaction of the driver with the road. It normally has only moderate, or even low, horsepower. It is usually not as practical an everyday car as the Mustang.

A Mustang is just not in the same category as, for example, Z3, Miata, Porsche, Cobra, or other sports cars. That is not saying it is worse, or better, just different.

I have owned Mustangs since Spring, 1964. They are great cars, in a class by themselves, now. Just not sports cars. Too big, too many seats, different purpose. Much more practical.

 

[TurboE]

As far as the wheel/tire package, in the late 80's the mustang and tbird had 16" wheel sizes available. "Most" cars didn't have 16" wheels they had 15" and some offer 16". So I don't understand the remark that the mustang shouldn't have 18" wheels (because it doesn't cost a certain price or whatever). Also I have 18" wheels on my car and lower profile tires, so the overall diameter is the same (i understand your calculation however you forgot about the tires, its a 17" wheel/tire package vs. a 18" wheel/tire package) so i dont see a huge inertia change, maybe very very slight due to the fact aluminum wieghs more than rubber. Those bigger profile tires also have rubber wieght that the lower profile tires don't have. So lets argue that it has a very very small effect, it handles a TON better. Don't get me wrong I understand the engineering part of it, I would rather it done correctly than just offer it because some customer wants it now but why not think to offer 17's and 18's initially, so your saying they designed a complete new car, but just couldn't get past the 18" wheel part....come on. However normally I don't like the factory wheels as much anyway so I would want aftermarket 18's anyway, although sometimes I like fords wheel designs. As far as the price argument tell me how much your 17" tires were, the last set of 18" tires cost me $120 a tire 245/40/18, thats not much, hell the stock 225/60/16 cost about $100. As far as wear "know what your doing" buy all-season tires or check tread wear ratings to get the type of tires you want. Traction vs. Tread wear, your buying them choose what you want. By the way, guess what would make the 18" tire prices come down even more.....if they were on mass produced mustang GT's, the more common place they are the cheaper they will be. To me a mustang is a sports car. You mentioned a "cobra" are you talking about an AC Shelby Cobra, or the 03/04 Cobra, that is simply a mustang with a supercharger and IRS. To me all the fast/sporty cars are sports cars, now if i lived in europe i might think an underpowered well handling car was a sports car, but i would also be paying alot higher gas prices and might be inclined to not have a V8. Maybe in the past you either had a fast straight line car or a well handling car, but now you can have both in one car..........

 

[MTU 5.0]

I'm disappointed by the wheels offered on the 05's. The 18's were by far the best looking wheels and should be an option at the very least. The bullitt style wheels are okay, but they don't seem to fit the new car as good as they did the 99-04's. And the optional wheels look like total crap IMO. They and the spoiler are the worst looking things about the 05's. (Everything else kicks ass!)

The first thing I would do If I got an 05' would be to put a nice set of 18 inch wheels and wider tires on, and then tint the windows. Third would be a good lowering kit. That would provide a real good look.

 

[SVTdriver]

Wasn't it already sai din this thread or another. That the problem did not lie with Ford on the 18's. That it was a supplier problem. At least that is what I have heard several times.