Do you know of any independent tests of various brands? I'm sure motor racing teams and other professional driving setups know, but as an ordinary car owner where would one objectively find out whether Firestone 123/45R56 or Dunlop 123/45R56 is nominally better? Even Which magazine decides it's too much effort, and just reviews them by the aesthetic value of their tread!
- Brands only matter a little. Most brands have a variety of price/performance offerings.
- For most drivers, more tread is better, and more channels (and a variety of sizes thereof) are better. CA roads don't shed water very well for example, so in heavy rains you need the tire to get the water out from between you and the road.
- Assume tire manufacturers are pareto optimal. Grippier, safer tires have lower MPG and expected lifetimes. The latter is usually somewhat advertised. Buy the 30k tires instead of the 80k mile options.
- If you're not driving in cold (<15F or so) weather, don't get all-season tires. If you are driving in cold weather, get snow tires (better, Nokian studded options don't tear up the road and offer excellent grip if they're legal in your locale). If you are driving in cold weather and not springing for snow tires, do get the all-season option.
- Properly inflated tires matter a lot more than you might think, making cheap tires outperform good options. Checking (or asking a mechanic to check for free) after any major temperature swings or every 3k miles or so is a good idea.
- Several tire sizes fit most rims. The wider options perform a bit better (total tire grip scales sub-linearly with road pressure, so distributing the weight over more area slightly improves grip). You won't pick up more than 3-5% with this parameter, but all-else equal (and if you don't mind worse fuel economy) it's good to know.
The best tires vary from year to year, and there's an inherent tradeoff between the different driving conditions you'll subject them to and how many sets of tires you want to keep around (most consumers want 1 set, most northern consumers at least recognize that 2 sets isn't a bad tradeoff if you have the space for as much of a grip improvement as proper snow tires offer). If you have a competent mechanic you trust, just tell them how you drive and ask what they would do for their car. They test drive a dozen cars a day and have a pretty good feel for what works well enough and gives you a good bang for your buck.
Actually answering your question now, AutoBild, Consumer Reports, Tire Rack, MotorTrend, and a number of other organizations test at least a few models (some of those test lots of models) of tires each year. Actually ranking the best from second-best is hard and maybe prone to bribes. Generally though, they provide objective measurements, and those measurements correlate pretty well with how the tire will handle when placed on your car. If a few choices are close, choosing based on what you can easily find locally or price or shipping or other factors is probably a good idea.
Increasing surface area decreases pressure (if mass/gravity/... are constant) and keeps frictional forces the same. The interesting question is what the limits of the system are -- when do you transition from static friction (ordinary braking) to kinetic friction (skidding/sliding), which dissipates less energy and doesn't slow you down as well.
The usual metric describing that transition is the "coefficient of friction." It describes the ratio of normal forces (your car pressing down) to frictional forces (your tire slowing down your car) at which you transition from static (good) to kinetic (bad) friction. Tires have a CoF which depends on the pressure (roughly car weight divided by tire surface area, complicated by the fact that wider tires don't necessarily have more surface area on their contact patches). As pressure increases in rubber tires, CoF decreases, so the same normal force (the gravitational force of your car pushing downward) results in less peak frictional force (the ability of your tires to stop you moving forward). Increasing surface area decreases that pressure, increasing CoF, increasing braking ability.
There are multiple parts to the braking system, and all play a part in deceleration.
1) Main slowing effect is braking system converting kinetic energy to heat dissipated by the brakes, and maybe back to chemical energy in the battery in the case of an EV with regenerative braking.
2) As the vehicle slows due to braking effect there's likely to be a mismatch between cars forward speed due to momentum and the rotational speed of the slowing wheels, and the role of tires is to try to maintain a grip on the road and prevent this from turning into a skid. Presumably there's energy being dissipated in the tires (and road) in the form of heat too, but only so much the tires can do if braking is too aggressive.
3) Either the driver, or anti-lock braking system, can pump the brakes to prevent the wheels from locking up since that's not the quickest way to stop.
So, tire contact area with road, and tread pattern, and tire material/construction will all play a role, but overall deceleration of the vehicle is based on a combination of all three of the above factors.
