Tire size usually follows weight distribution on cars designed to handle well. This explains why Mazda put the same width tires on all four corners (since it has roughly 50/50 weight distribution). More weight at one end dictates wider tires at that end to keep the handling balanced. Other things besides tire width affect handling balance, though, so there are many exceptions to this rule. This may explain why Mazda later put wider tires on the rear of the car, even though the weight distribution is still about 50/50.

-Max

 

hmm thats an interesting point.So which yeard did they go with wider tires in the rear and how much wider were they?

 

I -suspect- the larger tires on the rear had a lot to do with owners spinning the car too much. Understeer is much safer than oversteer (most people can handle understeer, but catching oversteer requires lots of experience and sometimes luck).

If you put different sizes on front/rear:
advantages: looks a bit nicer
safer (perhaps) handling
tires may wear more eavenly (or may not)
disadvantages: no rotation of tires
may be harder to buy only 2 tires at some places
you are the engineer, so you have to be extra careful

 

Well, It's 50/50 dry.

When u start to load the driver and even an additional passenger and a full tank of gas the weight starts to be rear bias.

Most people have their seats setup so that it's situated in the later half of the car.

Also, a stiffer suspension and a car with greater RWHP should warrant wider rear tires.