When it comes to tire size and gas mileage, there is a belief that there is a big difference in fuel economy if installing larger wheels, which is also known as plus-sizing. There is no denying that your vehicle may look cooler and more powerful, but what about performance benefits? Does tire size affect gas mileage is a good question, as in general the larger the wheels the heavier they are?
In that case, your vehicle will need more power and therefore more fuel. This means that plus-sizing may slow down the performance of your vehicle as well.
How does plus-sizing actually works?
The plus-sizing works very simply. When the wheel gets larger (in diameter), the size of the tire’s sidewall will have to shrink in order to maintain the tire’s overall diameter, which is very important. Why?
Keeping the overall tire diameter the same is the only way to keep the gearing the same as before and also the speedometer will be accurate. There is also a concern if the wheels and tires will fit within the fenders, which you don’t have to worry when tire diameter stays the same. Therefore, before you actually decide to go bigger, you have to check which and whether some parts may fit your car and your portable air compressor will have any use at all.
Does tire size really affect gas mileage and performance of my car?
As mentioned, bigger wheels do seem heavier, and in order to check this myth, it was necessary to test various wheel and tire combinations. This was the only way to know what you are getting and losing in the process of changing the tires size.
With the testing came the results that are not very surprising, but still will give you some thought about whether you should consider getting bigger wheels or not, and what do you care about more when it comes to choosing between comfort and looks.
Simply put, the answer on the question does tire size affect gas mileage is yes. When you get bigger tires, your wheel and tires will not only go bigger in size but also in weight which will have an effect on acceleration and fuel. This wasn’t a big surprise, but if you think about gaining bigger tires but at the same time losing a 10-percent in fuel and a 4-percent in acceleration is not a small number.
However, if you are for example thinking about 17-inch wheels, which are considered to give a braking performance, ride comfort, and steering feel, then you could consider 18s as well. This because 17 and the 18-inch wheel has no difference in the quality of the ride, but has an additional grip.
In the end, if you check which parts are good for your car, and if you decided to go bigger anyway, we still recommend that you should decide if you care more about the looks or comfort.
If you care more about acceleration and pleasant ride than the cool look, and you are not ready to spend a fortune on your fuel, then stick to your lighter tires.