Tires

By Brandon Baldwin

Tires!  The most important part of your car.  

The tires are responsible for holding the car up, getting traction to the ground for “go” and getting traction to the ground for the “whoow”.  They change the way we can go around turns, or not.  They even change the look.  Wide tires makes  the  car  look sporty, while skinny ones make it look like it is either classic or ready for winter.  

Speaking of ready for winter, it’s the pounds per square inch that makes one tire better than another in the snow.  You want the tire to have thinner contact patch to cut through the snow to the pavement.   Some people say they want “pizza cutters” for snow tires.  Snow tires are easy to identify with the small “snowflake symbol” on the side of the tire and many, many small cuts in the tread called “sipes.”  These “sipes” are what grip to the imperfections in the ice as they bend over to conform to the surface.  Most snow tires are even made of a different compound than summer tires.  That’s why they wear so quickly if you run them in the summer.  There are some all-season tires that work rather well in the snow as they have a small block design or many sipes, but nothing works as well as dedicated snow tires.  In fact, the best method is all 4 snow tires.  Historically people have mounted snow tires just to the drive wheels, but this results in impredicable steerability or stability.  Stability is the greater of the two.  Ever have the rear end come around when you weren’t trying to?  That’s lost stability.  That’s  why the best tires you have need to be on the rear for winter.  Most tire installers are required to tell you this, and won’t put new tires on the front.  

As for summer tires, many like stock size or larger in width or height.  The width is for performance cars where many people with trucks like a taller tire for increased height.  But, since this is the Seaway Cruisers with a majority of members with cars, we will address that.  When you install a wider tire on a car, you can stay with the original outter diameter so that the speedometer is still correct.  (Hey, maybe that’s why some of you get speeding tickets!) are larger outter diameter (tire is taller) makes your speedometer read lower than what you are actually moving.  Some will use GPS to get the right reading, while some will take their car to the dealership to be recalibrated, while others use the green mile markers while going 60mph for 60 seconds to figure out how far off their speedometer is.  

But, an increase in width makes a car look more performance oriented.  Guess what?  It’s not just a look.  If you want to get more grip in the summer on dry pavement, a larger contact patch (wider or taller) is the way to get that.  Greater width obviously creates more contact patch from side to side (racetrack cars), where greater height creates more contact patch front to rear on a car (dragsters).   There is one drawback though: wear and a changed contact patch.  This leads to the need for a customized alignment.  Increasing the width or height creates negative camber (tire tips inward more).  Even if the alignment specs are asking for a little negative camber to begin with, you still need to make it a little more positive (unless you plan to race with turns included, then there are different variables to consider, and if you want that, well, that would have to be another whole article just on that, and only one kind of racing at a time).  But, if you are a cruiser with a different tire size, get a customized alignment to go with your customized tire combination.  I’ll give you an old example.  I had a customer with an early 1990’s Chevy pickup that had 235/75R15 tires to begin with.  Then, he bought some wider rims and installed 275/60R15 which are the same outter diameter which will allow the speedometer to remain the same but give it a sporty look.  He asked for the alignment to be right to manufacturer’s specs, which I told him that would cause wear on the inside edges of his front tires.  Sure enough, a month later he complained about the wear and had me realign it.  I intentionally set it up for the extra tire width by increasing the positive camber.  He was happy then, well as happy as that guy could be.  You know what I mean.   Ž

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