Having made the decision of what kind of wheels to bolt up to the Clarion Builds 02 project, its time to discuss rubber. Now this might seem like a “who cares” topic for some people, but for those of us that have gasoline pumping through our veins, choosing a set of tires can feel as life changing a decision as the field of study we chose for our college major.

Now regardless of their level of car crazy, generally there are two types of tire buyers out there; those who buy OE spec replacements to maintain the factory ride quality of their cars and trucks, and those who have done upgrades to their vehicle’s wheels and suspension, where OE spec replacement tires just wont cut it. For either buyer, there are a few basic things you need to know that will help make shopping for tires a little easier:

  • The size of tires recommended for your vehicle. That can mean the factory recommended specs, or a tire that matches the tread width, series type, speed rating and load rating requirements for your car’s modifications
  • The climate conditions you will mostly encounter when driving. Does it snow or get icy in the winter? Will you be driving through mud or off-road?
  • Which are you most concerned about: price, comfort, gas mileage, performance or speed capabilities?

When we picked up our 02, the car came with 14-inch wheels and dry-rotted tires, however we didn’t buy the car for the wheels and tires and knew that during the build there would be a point where we’d have to decide on how to replace both. For wheels, we decided to upgrade the diameter from 14” to 15” and maintain the non-staggered wheel offset. Additionally, we knew we were also going to be modifying the car’s suspension, so would need a tire that would fit within our fenders without rubbing. After some measurements and calculations, we determined that the best size tire for the car would now be 195/50 R15.

Tire sizes 101:

  • The first set of numbers in the sequence, on our tires its 195, indicates the total tread width in millimeters.
  • The next set of numbers, which is 50 for our tires, is the sidewall aspect ratio. This number indicates your sidewall height as a percentage of the tire’s tread width. To calculate sidewall height, you take the tread width and multiply it by the aspect ratio. For example, the sidewall height for our tires would be calculated by multiplying 195mm by 50% (195mm x 0.50), equaling 97.50mm.
  • The following letter, in the case of our tires – the R, indicates the tire construction. R stands for Radial. 98% of passenger vehicle tires sold today are radials, so unless you’re restoring a classic car or buying tires for a commercial vehicle, your tires will likely have an R in the size.
  • The final number, in our case the 15, represents the wheel diameter. 15” is the size of our recently acquired BBS RS wheels.

Next, we needed to consider the road conditions that the 02 would encounter most frequently. Considering that we are in Southern California and only experience two seasons, warm summer and hot summer, winter tires are unnecessary, and for the same reason we could have easily explored summer performance tire options; however, with the suspension upgrades and reduction in sidewall size, we wanted to enhance the car’s handling characteristic while also retaining some of the legendary BMW ride comfort, and still be able to drive the car in any weather condition that the road could throw at us, thus decided to explore all-season options.

For the extreme car nuts, there are other things to consider when buying a tire, like load rating and speed rating, but the BMW 2002 weighs very little and is hardly capable of super car speeds, so those weren’t really anything we needed to pay attention to, though the 86V rating of our tires is more than ample for our application.

We want to give a special thanks to our program sponsor Toyo Tires for hooking us up with a set of Toyo Extensa HP tires for the Clarion Builds BMW 2002.

Alyson Yarberry