the 235/50/18 or the 245/45/19 ? or are they pretty much the same?

 

The 245 is technically 10 mm wider than the 235, however this is section width so not neccesarily 10 mm more tread width.

Depends on the tires too ...
18" are Pirelli P Zeros I believe, I'm not familiar with what Ford is using for 19".

Doug

 

If the 2011 is like the 2010, the 18" and 19" will both be Pirelli P Zero Nero All Season, except for the Brembo package which will get summer-only 19" tires. If a person's highest priority is drag racing they will probably want to buy an entirely different tire.

 

Depends, on what the actual diameter of the tire is?

Now for the tire wierdness - in a static state the total area of the contact patch is no larger or smaller despite the difference in size. However if the tire is both wider and taller then there is the possibility that the tire will deform significantly enough in a dynamic state that it will apply additional rubber to the ground.

If the tires are the exact same diameter then its a wash and the 245/45R19 is only of real benefit in lateral acceleration (or perhaps at a disadvantage since the sidewall is shorter and less compliant).

But thats justg looking at it from a tire size standpoint, there still is the matter of how much actual rubber hits the road (based on the tread design and internal construction) and how hard or soft the compound is

 

the thicker the tire the better. It's kinda splittin hairs, but the 19's on paper offer the best.

If you're willing to go aftermarket there are thicker outputs that can work. Keep the fronts the same at 245/45/19 and you can go 275/40/19 in the rear

Check out http://www.1010tires.com/TireSizeCal...?action=submit to see if it's safe or not.

But yea, wider is better! (but within the limits of course)

 

both are the same brand --Pirelli P Zeros that Ford installs to there stang..i would handling and hooking up from a complete stop.

 

Keep in mind most of the supercars are mid engine. They needed those wider rear tires for handling purposes - not launching.
And while a wider tire on a Mustang would help on launch, at some point doesn't the increased friction slow you in the quarter mile?

 

wheel spin is wheel spin... I would think that they don't cause decrease in 1/4 mile. These front engines blaze the 1/4. Granted they crank out outrageous hp/tq. But still... I don't think front/mid/rear engine layout matter in wheel spin. Nor are they special cases for handling as many front engine supercars have bigger tires than mid engine super cars.

Front engines:
The Mercedes Sl65 AMG: 285/30/19
The corvette ZR1: 335/25/20
Aston Martin DBS: 295/30/20
Dodge Viper: 345/30/19
gt500: 285/35/19

Rear/mid mount:
Ferrari F430: 285/35/19
Lamborghini Gallardo LP560-4: 295/30/19
Porsche 911 GT3: 305/30/19

That old Countach is a rare example of outrageous...

 

the difference between the two is 0.4 in width.