First off, the calipers. What they are - is a 6 piston monoblock (A), double bridge (B) and 6 padlit design with an external fluid crossover. Generally speaking, all of those headlines read to a very capable caliper. The problem is this caliper drags tremendously. A quick explanation on what Brake drag is. When you release the pedal but the brake pad doesn't release fully from the rotor. This creates heat, kills power, and dramatically lowers top speed. overall bad.
Next, the hat area of the hat takes a curve inward. This might be for sound reduction or something else. All the rotors on the market that curve inward like that have a tendency to crack often and violently. S2000's have the same issue and share the same inward swept hat.
What to do about it.
At the Minimum Get yourself a rotor that has corrected the engineering flaws in the OEM rotor. The fastest way to reach that goal is to get a "two piece" rotor. DBA comes to mind along with others like AP.
GM decided to go with a padlet design. in each of the front calipers, we will find 6 individual pads. the aftermarket does offer "one big pad" that takes the place of all the padlets. Through personal experimentation and collaborations with other brake guys, the consensus is that the padlet is the shape to keep. and here is why.
|here is a poorly drawn caliper pushing a blue pad into a rotor. Please excuse the lack of art skills.|
When you have a very big pad in a caliper you'll get some issues. Much like a bolting a cylinder head to an engine block, a pad will distort under pressure. In the first picture (left), the pistons will push down on the blue pad and make it distort under braking. This picture is clearly an exaggeration. Once the pad is distorted it will return to its original shape, leaving high points on the pad face. The high points can induce more brake drag (right). the padlet design is much more capable avoiding these high points and reducing drag.
for track drivers, it is critical to your vehicle's longevity that you run a "square" braking set up. Square means the same compound front and rear. why that is insisted uppon, is becasue if you have a higer Tq front pad you will have more of the braking duty done by the front axle. this equates to more heat and a shorter life for the rotors.
the Nuclear option is to get a Big brake kit, put all your worries aside. lets list over the pro's and cons.
- fantastic caliper, american made
- very well supported by aftermarket pad companies.
- rotors are low quality,
- Pads are taken from Porsche road cars Expect to pay big money for track pads. $500+ ea
- Get the radical caliper, it's 2017 tech,
- Similar kit used by corvette racing
- too many choices! AP has 4-5 different kits for the z. avoid all of them and get the 370mm radical kit.
- The rotors are balanced improperly.
- Keeps padlet, Big nasty 4 piston calipers,
- Made in the USA quality on rotors and calipers.
- lead time is 9-10 months,
- replacment parts are in short supply,