big-brake-kits

StopTech 81.B39.9921 - Drilled Aero-Rotor Kit Front

rating-star review rating-star review 1rating-star review 2rating-star review 3rating-star review 4

Unavailable

This product is currently unavailable.

Check to see if this fits your vehicle

This part fits

  1. 2016 BMW 335i GT xDrive
  2. 2015 BMW 435i Gran Coupe
  3. 2015 BMW 335i xDrive
  4. 2015 BMW 335i GT xDrive
  5. 2015 BMW 335i
  6. 2015 BMW 435i xDrive Gran Coupe
  7. 2015 BMW 435i xDrive
  8. 2015 BMW ActiveHybrid 3
  9. 2015 BMW 435i
  10. 2014 BMW 435i xDrive
  11. 2014 BMW 335i
  12. 2014 BMW ActiveHybrid 3
  13. 2014 BMW 435i
  14. 2014 BMW 335i GT xDrive
  15. 2014 BMW 335i xDrive
  16. 2013 BMW ActiveHybrid 3
  17. 2013 BMW 335i Sedan
  18. 2013 BMW 335i Sedan
  19. 2013 BMW 335i xDrive Sedan
  20. 2013 BMW 328i xDrive Sedan
  21. 2013 BMW 335i xDrive Sedan
  22. 2012 BMW 335i Sedan
  23. show all...
Authorized Dealer

About this product

Part #: 81.B39.9921

StopTech AeroRotor Replacement Kits ARK are designed to replace your vehicle's original factory rotors, while retaining the factory brake calipers. Although the ARK is the same diameter and thickness as the factory rotors, it offers improved cooling, braking, and handling. The directional, floating AeroRotors allow independent expansion of the rotor and hat without "coning," thanks to elongated drive pin holes. ARK components include AeroRotor friction rings with patented internal vane design, pre-assembled to billet aluminum AeroHats with directional stand-offs that optimize cooling airflow. The patented AeroRotor vane design pushes up to 80 percent more air than factory rotors for better cooling and reduced fade on the track. The aircraft-grade aluminum hats and 2-piece AeroRotors are up to 8 pounds lighter than stock rotors, allowing faster acceleration and deceleration, and improved handling. StopTech AeroRotors are available slotted or cross-drilled. These slots or holes allow better dissipation of heat, friction material and debris, assuring that fresh pad material is in contact with the rotor every time the brakes are applied. An optional anti-corrosion, zinc finish is available for customers in cold climates, where salt and chemicals are used to melt snow and ice. The zinc coating also benefits customers who prefer no visible surface rust on the vanes and outer circumference of the rotors. StopTech AeroRotors are 100 percent made in the USA.

More Details

PositionFront
StyleDrilled

See what our community says about stoptech products

Ryuku Ventura

158

Ryuku Ventura
2014 Ford Fiesta
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
Wanted to improve braking performance.
Is this your first time buying from this brand? Did you consider other brands?
First time; would buy again. Considered EBC however the Stop tech axle pack seemed to be a better idea for my budget.
Was it easy to install? Any installation tips that will help others?
Moderately easy. Be sure to have a brake caliper tool.
Once you've had a chance to use the product, did it meet your expectations?
Met expectations; great rotors, pads can use an upgrade later.
Any additional comments?
Very spongy brake feel for the first few days of driving but does get better. Be sure to use the proper break in technique (10 repetitive hard braking from 60mph - 10mph consecutively).
View on Ryuku's build
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
LMR didnt stock HP+ rears for my car so I just went with these
Is this your first time buying from this brand? Did you consider other brands?
yes, wanted HP+ but LMR didnt have any. Would also consider EBC next time if these arent great
Was it easy to install? Any installation tips that will help others?
yep just flip caliper over and slide new pads in
Once you've had a chance to use the product, did it meet your expectations?
we'll seee
View on Andrew's build
Jack Gennuso

215

Jack Gennuso
2001 BMW M5
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
Good price and they work very well. Low noise level, good cold performance, and decent feel and bite.
Any additional comments?
Make sure that you bed the brakes properly (Stoptech has a tutorial on their website) for rotor longevity. These pads do make more dust than OEM.
View on Jack's build
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
Came packaged with my wheels. A bit overkill for the truck imo. I wouldn't buy it brand new for this type of vehicle.
Is this your first time buying from this brand? Did you consider other brands?
Yes, first BBK I've ever bought. I did not consider others at least for this car I didn't.
Was it easy to install? Any installation tips that will help others?
Yes, it was easy once I had all the right parts. I was missing the SS lines at first and the stock SS lines wouldn't fit the caliper properly. I bought porsche brake pads instead of stock stoptech pads.
Once you've had a chance to use the product, did it meet your expectations?
Yes it does. Brake feel is much better than stock.
View on Tuan's build
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
I tried to have my slotted rotors machined, but it was too warped that braking caused severe vibration reverberating through to the brake pedal. Not Good. I needed a cheap replacement ASAP.
Is this your first time buying from this brand? Did you consider other brands?
No. I had the slotted rotors, but I tried to save money by just buying pads. Not a wise choice.
Was it easy to install? Any installation tips that will help others?
If you can turn a bolt, you can install this part.
Once you've had a chance to use the product, did it meet your expectations?
Definitely a good rotor.
View on Claude's build
California prop 65 warningWARNING: Cancer and Reproductive Harm www.p65warnings.cs.gov

*Some manufacturer restrictions apply.

shipping-worldwide from warehouse

we ship worldwide!

Based in California with 3 warehouses across the country, we’re sending out shipments everyday of the week, even Saturdays. Because your next mod shouldn’t have to wait.

+ FREE GROUND SHIPPING ON U.S. ORDERS OVER $99
Globe international shipping icon
Have a question? Ask an Expert!

Finding the best parts can be tricky

- but not to worry! Our team of experienced American Muscle, JDM, Euro, and off-road tuners are ready to answer your questions (as long as we’re not in the garage wrenching on our own builds).

Decorative testimonal quote icon

What do you get when you mix Facebook, Amazon, and your favorite online car forum? You get Wheelwell.com.

undefined supporting their testimonial

Hot Rod Magazine

Decorative testimonal quote icon

Wheelwell helps you organize all your stuff for your car, I’ve loaded all my cars on Wheelwell and you can see all the parts I’ve put in them and that may help you make a decision with your own build.

Matt Farah supporting their testimonial

Matt Farah

The Smoking Tire / The Drive

Decorative testimonal quote icon

This is an awesome new site where enthusiasts can get together and figure out what products work best on their ride.

undefined supporting their testimonial

The Truck Show Podcast