Big tires/rims and braking distance

[Madtiger]

How Heavier Wheels and Tires Impact Braking Distance - Beefed Up Brakes

Are you adding a set of wheels and tires to your vehicle that are heavier than stock? If so, you might be wondering how they will impact the performance of your brake system. In this article, we’ll explain: Why wheel and tire weight has an impact on brake performance What math shows with regards to…

www.beefedupbrakes.com

I found this article.

The “10-10-10-1” rule:

• A 10% increase in overall wheel diameter works out to a 10% decrease in brake performance
• A 10 lbs increase in wheel and/or tire weight works out to a 1% decrease in brake performance

Is this accurate? So, increasing the diameter by 10% (if everything else being equal) is much worst than putting on heavier tires (of same diameter). Of course, if you add bigger AND heavier tires, then that is really a problem for your stock brake system.

 

[Cruisin911]

I'm sure those are generalizations. It is simple physics though that if you increase the overall diameter of your rolling unit (setting aside the weight factor for now) that your braking performance effectively decreases, resulting in longer stopping distances. The only way to overcome this is to increase braking capability with larger rotors and pads (setting aside clamping forces) to bring that distance back down. Crux of the slippery slope argument.

 

[gaijin]

Bigger/heavier tires buy you:

- Longer stopping distance
- Lower gas mileage
- Slower acceleration

Hard to put specific percentages to these, but the bigger/heavier the tire is compared to stock, the larger the percentage negative impact.

Hey, it's the science

HTH

 

[TrekboxX]

You only lose stopping distance if the brakes are no longer able to threshold brake with the larger tires or the coefficient of friction is reduced. The other factors are correct. You would only increase braking distance by X percent with the diameter increase if the brakes were only "just" able to threshold brake with the stock size.

Most modern vehicles have excess brake power, so a reasonable increase in tire size has little difference on stopping distance. But brake fade, brake wear, slower acceleration, etc. are all definitely factors.