Wider Rear tire versus traction/wheel spin?
 

I keep reading that wider tires don't offer better traction, due to the vehicle's weight per square inch being reduced and redistributed over a larger contact patch. From a purely theoretical physics standpoint, I understand, but in the real world where (most of) you and I live, I want to know the truth.

Has anyone here put wider tires on the back of their Mustang in search of more traction, and found what they were looking for?

I have a 2015 GT W/O the Performance Package, so I have 255/40/19s on the back, with the standard limited slip diff. In first gear the rear tires spin quite a bit, slowing down 0-60 times. I'm guessing I could knock off a full second if not for the tire spin. I'm thinking about putting 295/35/19s on the back, as they are the same diameter as the 255/40/19s.

Any thoughts? Anybody have a first hand experience comparing wheel spin in the Torsen-equipped PP versus non-PP GTs?

Thanks!

On one hand that is true, but on the other you have to consider the contact patch area times friction coefficient, and the latter wins.

My GT TP came with 255s all around. I upgrades to 275s all around (keeping square for road course use), but the straight line launch improved. And if it makes you feel any better the '15 + PP cars come with 255 front and 275 rear.

The trade offs of wider rear are:
1) Asymmetric wear and inability to rotate
2) In full lat corners to take advantage of wider rear you need a bigger sway bar on the back of the car. But in straight line it's not an issue.
3) FI guys always have wider rears due to more power 315 or wider even.