... a big brake kit:

1. Thermal capacity: Big brakes can absorb and shed tremendous amounts of thermal energy. If you are not experiencing fade with your current set-up while at the driving schools, then this is not a reason for you to upgrade. As your skills improve, however, and if you start using R-compound tires, the amount of energy converted by your brakes will eventually be greater than their capacity at which point you will either back off or upgrade.

2. Pedal feel: Just like a short shift kit makes the shifting tight, the Dinan Stage II swaybars and springs make the handling feel better, and a big, fat steering wheel makes it feel nicer to steer, the big brakes make it feel better to brake. The pedal has less travel overall, the throw before braking begins is shorter, and the brakes are easier to modulate. This is becuase the braking response of a fixed-mount, multipiston set-up is much better than the floating, 17 pound cast iron caliper used in the stock 540i brakes.

3. Reaction time: when you hit the brakes in a panic stop (meaning you weren't expecting to have to hit the brakes) you will begin to brake sooner. This is because of the reduced pedal travel and the near instant linear response. This can result in reduced stopping distances. For example, your car travels about 24 feet in 0.2 seconds at 80mph. On the track, however, reaction time is not as important since you know where you need to start braking, so the driver can anticipate the delayed onset of braking and simply hit the pedal sooner. Reaction time improvement is primarily a street driving benefit.

4. Convienience: It's much easier to swap pads in a big brake kit. You can do it in just a few minutes per corner. The caliper does not need to be removed. Just pop off the spring clip and yank out the pads. Slap the new ones in and you are good to go. Makes changing from street pads to track pads not much more of a deal than changing from street wheels to track wheels. Also, a huge variety of racing friction choices (pads) are available for the Brembo and StopTech calipers.

5. Looks: They simply look stunning. I have to admit, I factored in appearance when I upgraded all four corners of my wife's 2001 540i/6. She wouldn't even consider letting me get red calipers up front if I wasn't also going to upgrade the rear to big brakes.

The best way to make a decision such as this is to see if you can drive a car with big brakes. Check around on Roadfly or ask the organisers of your club events if they know anyone with an E39 and Brembos or StopTechs installed. It's not unreasonable to want to check something as expensive as this out before you order it.

Dave Zeckhausen
Ridding the world of CDVs, one E39 at a time!