I’ve had my Alcon front Big Brake Kit (BBK) for well over a year now, but am just now getting around to reviewing it. Why the delay (I typically do a blog review of each mod within a month or so of install)? A BBK isn’t for everyone, and the true benefits of it are really only appreciated on the track – sadly I went a long time without a track day, which meant it wasn’t until just last weekend I had ample experience to give this mod the review it deserves.
Kit Fit & Finish, Install
We’ll start with the easy stuff – the Alcon BBK sold by STaSIS is a very solid kit. It contains everything you need to install, including detailed installation instructions. A few friends and I knocked out the install in a driveway in about 2 hours, which I condensed to a one minute time lapse above
Alcon makes some of the lightest and highest performance calipers in the business, and their crescent groove rotors are known to be nearly bulletproof as well. While Brembo and Stoptech both make similar BBKs for the B6/B7 platform, the Alcon kit is one of my favorite as its a much lower price than Brembo, easier to change out pads than Stoptech, and arguably the best metallurgy out there. I happened to come across my kit used and heavily discounted, which made the decision a no brainer.
The real decision point for me was: 350mm or 370mm rotor size, and 4 piston or 6 piston calipers. While I’d obviously love the 370mm 6 pistons, I don’t track enough to really justify the performance increase of the two extra pistons and like I mentioned before, I found this on sale. The 350mm 4 piston kit is also a very good option and saves a little weight over the 370mm rotors if you’re only an occasional track driver like myself.
And while I probably don’t need to detail out the advantages of a BBK in general, I’ll do so anyway:
- OEM calipers are one piston, these are four (or six)
- Much higher maximum temperature rating, so capable of running track pads without frying pistons/rings/etc.
- Lighter calipers and rotors over OEM
- Stainless steel lines improve braking under heat
- Larger vented rotors also improve cooling
- They look cool (I don’t really care, but sadly many people buy for this reason alone)
- And last but not least: very easy ability to swap brake pads
This kit really shines on the track, for a number of reasons. My favorite part is that not only can these calipers & rotors withstand the abuse of a track pad that goes well over 1,000 degrees in temperature, but you can swap between track pads and street pads by removing two allen bolts, a process that takes about as long as removing the wheel to get to the brakes in the first place. Simply use a 10mm Allen socket to loosen the caliper from the caliper carrier, pop out the old pads, pop in the new ones, and then retorque the bolts to 70 ft/lbs. The only word of caution is to not over torque these bolts – my friend has stripped his by doing so. Photo below borrowed from Quattroworld here. If you’re going to track your car, a BBK is ore than a good idea…the S4 is a VERY heavy car, so your brakes take a solid beating. While I’ve done a track day on OEM brakes, pads, and fluid, and was even impressed with how well they did, if you’re on OEM brakes it’s definitely the first part of the car to start to break down and fade, and doesn’t inspire much confidence. With the Alcon kit, I was late breaking and still going hard at the end of my sessions and the end of the day with zero worries as to whether I’ll have fade or issues. If you’re on the track, whether in your car or a rental from U Drive Cars, a BBK is more than a good idea…
While the kit shines on the track, it’s great for street driving too. You won’t feel a ton of difference over the B7 S4 brakes at first, and to be honest the OEM brakes are very robust and more than sufficient for 90% of S4 drivers. If you’re looking to save money, going with lightweight rotors, stainless steel lines (along with better brake fluid), and more aggressive street pads should be plenty of upgrade for the occasional canyon run or spirited cruise. That being said, this BBK is great on the street – with Carbotech Bobcats (1521) they are very low dust, very quiet, and still have plenty of bite when you need it. You can drive with confidence knowing that if anyone brake checks you, you’ll be able to stop on a dime…or as a Facebook friend said “stops so hard the world stops.”
They also DO look cool. I don’t think that should be a reason to buy them, but if you’re rocking a $6,000 set of HREs and have some puny rotors behind it, I do think you’d be silly not to at least invest in some Adams Rotors and paint your calipers if not a full on BBK so you don’t look wheel rich and brake poor…
Brake Pad Choice
I’m running the supplied Carbotech Bobcat 1521 brake pads front & rear, and then running Carbotech XP10s in front and XP8s in rear for track duty. I went this route after speaking with a lot of friends who have similar setups, as the logic presented was pretty sound:
- The Carbotech compounds play nicely with each other, so you can switch between pads without having to turn the rotors or do any crazy bedding procedures
- The Bobcats are phenomenal street pads (VERY low dust, very low noise)
- Carbotech has a number of track pad options, all of which are fairly rotor friendly
- They’re affordable, widely available, and have a great reputation in the industry…
Brake Fluid Choice
I like Motul RBF600. It seems to be what a lot of people are running, its got a high temperature tolerance, and its cheap on Amazon. I keep a spare bottle on hands at all times, and its a fluid I’d recommend regardless of whether you have OEM brakes or an aftermarket BBK.