The Autoblog Project Garage: Big-brake install, Part 1

Despite its 4200 lbs of "road-hugging mass", my '96 Chevrolet Impala SS manages to handle an autocross course with surprising grace and agility (that is, if one wants to apply such adjectives to an obnoxiously loud sedan that negotiates cones by frequent and well-timed applications of full opposite lock steering). Get it onto an open track, and then it's yet even more able to put its considerable power and adhesion to good use - for all of two or three laps. That's when the brake fluid reaches its boiling point and the pedal sinks to the floor, which is surely one of the most sickening feelings one can experience in an automobile.

I've already upgraded the stock brakes with Raybestos rotors that have thicker "cheeks" than the stock parts, and a set of Raybestos BruteStop pads live up to their name while providing friction (and rotor wear) similar to that of 80-grit sandpaper and a terrible amount of squealing and brake dust. The stock 95/5 front/rear braking bias was also modified to a much more reasonable 70/30 via a simple proportioning valve modification. Even when hot, the upgrades deliver sufficient stopping power and cured the vehicle's rotor-warping habit, but a 12" diameter and 1" thick rotor simply does not have sufficient mass and surface area to dissipate several hundred kilowatts of power many times per lap. Quite simply, the performance of the brakes have failed to keep up with the rest of the vehicle.  

[We've got far more reading on brake system options for the Burgundy Boat after the jump...]

Let's set some ground rules here. First, we're not going to dork around with rotors of the stock size, no matter how many combinations of holes, slots, and cryogenic treatment are offered. We're operating on the principle that removing material from an already-inadequate system is not going to yield favorable results, and the plethora of horror stories surrounding drilled rotor failures only serves to reinforce our feelings on the topic. This leaves me with but one choice - figure out how to stuff the larger rotors behind the Impala's five-spoked 17" wheels.

Fortunately, several options exist for the Impala, despite the fact that it isn't a "traditional" performance vehicle. Baer Brake Systems seems to make kits for just about anything on four wheels, and it has two options available for the Impala. The budget-oriented GT system is based on the two-piston sliding calipers from GM's 5th- and 6th-gen Corvettes, and utilizes a 12.75" rotor. It comes in at $1900 (note that several discounts can be found on Baer systems, which may substantially reduce this price). The $3600 Extreme Plus utilizes 6-piston calipers and 14" rotors to provide additional stopping power and thermal capacity, but unfortunately also require larger wheels.

Stainless Steel Brake Company (commonly referred to as SSBC) has been in the business for a long time, and offers several options for the GM B-body. The only system offering a net increase in rotor diameter is the $2200 Force 10, utilizing a 4-piston caliper and 13" rotor.

TCE Performance Products was one of the first to offer a budget big-brake system for the Impala and its B-body brethren, employing a 13.1x1.25" two-piece rotor mounted on a hub which itself is a turned-down stock rotor. Four-piston Wilwood calipers are used, for which a wide variety of pads are available. $1700 buys the (very) complete base system, while 6-piston calipers and 14" rotors in either 1.25" or 1.375" widths will bump the price another $500.

Another "early adapter" in the B-body world was Mov'it, who specializes in applying Porsche components to a variety of vehicles. Its catalog includes systems with rotors as large as 18x1.5", which means that one's imagination is only limited by wheel size and wallet thickness. The B-body system, which is no longer available, was based primarily on the Porsche 993's 13" brakes. Included were "drilled" rotors, which were actually cast with holes in place to eliminate cracking. The performance was exceptional, as was the price - and the increasing value of the Euro did nothing but hurt.

For those willing to let the metal chips fly, larger brakes can be had for significantly less than the cost of a "turn-key" system. A large variety of calipers, rotors, and hats can be purchased from hardcore circle-track and dune buggy parts vendors, but the caliper brackets and hubs (for those vehicles that integrate the wheel bearings and studs into the rotor) will tend to be a DIY prospect. The process for making hubs (where necessary) is a simple matter of chucking a worn-out rotor in a lathe and removing the braking surface, leaving behind the bearing carrier and the wheel-interface surface. Over this can be slid a one-piece rotor or rotor-hat assembly of your choice, provided that it matches the hub's bolt pattern (if not, it's easy enough to modify the rotor or hat to fit the hub).

A few friends and I have been talking about building such a system for our vehicles for a couple of years now, but while we were standing around the car jawing away, some folks in the GM G-body community were actually building parts. This DIY system was built using the taller spindles from a B-body, turned-down rotors, and Corvette C5 components for about $800 - a substantial savings over a commercially-purchased big-brake system. Other rotors and calipers could be substituted as one's wheels and budget permits. This was the path of choice and the next big science project on my list, until I recently stumbled across another option.

Kore3 Industries is a rather young company serving the performance brake segment, but one that seems to be making a name for itself by offering low-cost components and systems for some of the less-common domestic vehicles. At the heart of its B-body brake kit is a set of hubs that are fabricated from billet, instead of turned-down rotors. This allows for a longer registration feature that centers the wheel on hub-centric wheels, so that proper wheel mounting can still be maintained after slipping a rotor over the hub. Brackets are offered to mount Corvette C5 calipers to the stock knuckles, which must be modified by the installer. Modified rotors to fit the vehicle's 5x5" lug pattern are also offered, or aftermarket rotors can be selected according to the vehicle's usage. In fact, the purchaser has the ability to purchase each of the components in the kit separately, allowing it to be exactly configured as one wishes.

I selected a complete kit using the 12.8x1.25" rotors, red-colored Z06 calipers, hubs, and miscelleanous other components required to install the system on my car. $1085 worth of damage to my credit card later, and something like this should be on the way:

Note that we ordered the kit with "blank" rotors, not the drilled and slotted parts shown above. Needless to say, I'll be eagerly awaiting the arrival of the big brown truck in about a week, and we'll be following the install once I get around to it. Stay tuned...

More Information