I am looking to improve consistency of my braking at the track with my e46 M3. What are the advantages of 6 piston calipers? Is there significantly more feel? I saw a write-up on my car specifically and the 6 piston upgrade increases front bias by 16% vs 9% with 4 piston brembo set up. I want to be sure that this change in bias will not adversely impact on stability and braking. 4 piston caliper is not a monoblock caliper whereas 6 p is but of course weighs more. I am not into bling just performance. Someone told me 6 piston setup can overwhelm rest of brake system on car?? Also, which manufacturer is best. I get the sense that brembo is somewhat better vs stoptech. Some guys really love alcon?? Any suggestions on a brake guru to chat with? Thanks.

 

There's a ton of misinformation out there if you are searching on your own. In order to filter through it, the best advice I have is to take the "rumors" about a particular company or product straight to that company or manufacturer of the product.

Example:
The information you have about the Brembo 6-piston or 4-piston kit being either 16% or 9% front biased is incorrect and probably a bit confusing. You talk to the guys at Brembo and they will correct the false information and put things into perspective...you talk to someone at another brake company and it's in their best interest to not clear up that misinformation and it helps them sell you on their product.

For the E46 M3, the difference between 4-piston and 6-piston will pretty much come down to 3 things.
(1) Wheel fitment
(2) Replacement costs
(3) Performance and longevity

If you can't physically fit the 6-piston under a particular wheel it becomes a non-option. If you can fit either option then that leaves the other factors wide open. Before you can get a proper answer to either of those, it would be important to gather more information about your experiences with the factory brakes, your intended usage with the car, current modifications and future plans, and your overall goal with this upgrade and your car.

Brembo is "arguably" the best quality and longest lasting product across the board. The only reason I say "arguably" is because every other company trying to sell a brake kit will say other wise and try to promise the same thing. Brembo is the number one selling bake product in professional racing and aftermarket, as well as the #1 chocie for automakers and supercars around the world, for many different reasons. The first and most important is that you can't physically make a better performing and longer lasting product for less.

Which in turn creates the best question you could ask when looking at other braking products..."How can a product be less expensive while claiming to be just as good, or better, last longer, and require the same or less mainenance? All while at the same time not being recognized for it by the most discriminating customers int he world?"

 

The Brembo 6 piston kit front 4 piston rear makes the M3 E46 really stop. Stock BMW brakes are a complete joke at the track. Brembo customers service is excellent. Don't even think twice about this upgrade.

 

Considering there are many street cars that run fine with 4 piston setup on the tracks, you should be fine with a 4 pot system. If you are switching from a stock setup, consider a systems that's closely matches the piston size you're replacing. That way, the brake bias will be closely matched. If you go with a larger system (requires pushing more fluid), you will need to adjust the bias to compensate.

As for brake manufacturers, Brembo, Alcons have been around forever and found on many race cars. Naturally, they demand a premium. Stoptech has made a name for itself amongst the enthusiasts and amature racing circle. I don't have them myself, but with many friends who run them on either street cars that do tracks on weekends to full track-prep cars that are trailered. Despite lower price point, Stoptechs, with the two-piece by design, are better (in strength) than monobloc designs found on modern-day sport and sporty cars.

Which should you go with? IMO, you can't go wrong with Brembo, Alcon, Stoptechs, or even (to some) the lesser known Wilwood. Picking which brand depends on how long your arm is (how deep you can reach into your pocket for $). FWIW, the 370Z NISMO comes stock with those gold-color Brembos. Car & Driver recently lost brakes on the Nismo during their Lightning Laps event, only stopped by a wall. They said the cause was limited cooling and bad pad choice. So, you can have a brand name brakes, and bad things can still happen if the rest of the system (rotors, pads, cooling, etc.) is sub par. BTW, the right pads will give you the pedal feel, not necessarily the caliper itself.

Sorry fro the long winded babble... but brakes are critical (more so than HP). So hope this gives you enough rope to start your research and not hang yourself.

 

PM sent with info.

 

I have used Alcon 6 pot 4 pot and it is one of the best upgrade for M3.. Stock brakes are joke not just on the track but even on the street.

Instead of braking at 200m back straight at shannonville i was able to brake right before 50m consistently without the need to pray if the car can really stop and that is without using racing pads.


The biggest advantages with 6 pot is wheel clearance. It is thinner than 4 pots so you can fit stock 18" without any issue.

Alcon is more rear bias than stock, so it changes the weight transfer while braking and I prefer that more than the stock setting.

 

Have you looked into Tar-ox? they have selections ranging from 6-16 piston kits