At minimum I'd recommend adding the bullets below to your list. These are some of the most critical factors when examining brake wear rates. After each I've listed why they should be added.

• Tracks being run - Tracks vary wildly in how difficult they are on brakes. Willow Springs is a completely different can of worms than Road America or Watkins Glen in terms of brake abuse and use. Fast tracks with long straights, followed by heavy brake zones down to a slow speed will chew through brakes much more rapidly than flowing tracks with lots of S turns, mid-straight chicanes, and sweepers.
• Tires being run- Tire choice is huge with regard to brake wear. Hoosiers will allow you to inflict far more abuse on your brakes than a 400 UTQG street tire.

Frankly, predicting brake wear is a daunting task. Our customers ask us this question over and over...and over! There is a laundry list of variables that impact brake wear, some of which are a bit subjective. Driving style is one of them, and an important one. If you put two different drivers in the same car, you're likely to see different brake wear rates. We see this all the time in pro racing. One guy crushes a given brake setup, while they work great for a different driver.

One more note about brake ducts. Again, ducts are a complex issue. In this list the assumption is that brake ducts are actually lowering the disc and pad temperatures, and providing greater longevity. In reality, many of the home-brew duct kits we see actually hurt performance more than they help. A lot of times they blow air into the wrong areas, aren't collecting adequate air from the front of the car, aren't adequately transmitting the cooling air they do catch into the center of the disc, and the mounting mechanisms many times trap heat against the inner disc face. All of those potentially add up to increasing pad and disc wear rates, rather than decreasing them. Therefore, using brake ducts as any type of predictive factor for brake wear rates is darn near impossible.

Hopefully the above is helpful. :)

I agree trying to dial in on exact $$ isn't practical and maybe not real useful. That said this discussion has helped me determine that I can expect roughly 3 times thevpad life from a BBK, which then helps me come up with an return on investment that I can then present to my wife as justification to by a new BBK :)

it it also helps discuss the various BBK and pad options and look at possible combos that are more cost efficient. I can tell you that a couple of kits I a steering clear of based on the cost of pads and cost of future maintenance (rotor rings, rebuild kit, etc). When 75% of the reason for going with a BBK is to save $ a thread like this is helpful.

anorexicpoodle on here has the ST40 kit and is on over 80 (and possibly over 100) track days with his rings using st43 pads. He has yet to replace is rings

I am going to try URGE flow rears with OEM fronts and see what I get. I figured I would buy these if I went with a BBK anyway so I might as well try them first. If these increase pad life I might even consider Giro disc front rotors and skip the BBK. Anyone who has tried this setup have insight on pad wear??

After about 18 track days, a bad pad selection and a weekend at Circuit of the Americas sent me on a path to replace my rotor rings. The worst crack was 0.75", rotor thickness was 27.5mm, but the grinding and pad deposits put the nail in the coffin.

My URGE rotors still look pristine, albeit a little thinner.

The driver also makes a huge difference in brake pad usage. If you're running r-comp tires and winning NASA time trials on a regular basis you're going to go through pads much quicker than the typical weekend track guy. But I do agree that a BBK will pay for itself if you track enough.

I was going to install the Stoptech BBK but see that a set of rings is now close to $600 up from around $450 last fall. The Girodiscs went up a lot too. Did the price of steel go up? I thought it was still cheap - the recycling yards barely pay anything for it.

-Kit: Trophy Kit
-Pad: Winmax W6--$180 I think- 9 Days so 9hrs? Still have 80%
-Brake ducts: No

-Rear brake kit: URGE
-Pad: Winmax W6--$160 I think--8 Days 8hrs? Still have about 50%

-Estimated street driven miles- 1000miles to and from track

-Kit: V8 Roadsters Prototype Kit (STR-43 Caliper, 328mm x 28mm 2-piece directionally vaned rotor) - $1900
-Front Pads: GLoc R16 - $250
-7 hours so far, estimated 18 more days of track time left on pads (2 hours/day)
-No brake ducts


-Rear Brakes: OEM Rear Brakes
-Rear Pads: GLoc R10
-8 days (2 hrs/day) on pads
-7000 miles total on kit, mixed street/track driving.

No, but product liability insurance sure has.