My friend Bill kindly provided his take on the test drive he and Jen did last week in my 911. As you can see Bill really knows a lot about high performance cars. He races them. Bill thought that my brakes did not grab as tightly as he would have expected. Also I have drilled brake rotors on the 911, which is more for appearance than anything else. As always, this is an opinion presented below, not necessarily the right thing to do for everyone. Some people really love the way drilled rotors look, for example, even if they don't enhance braking performance. Like Bill, I LOVE the stiffness of the brake pedal too, and I do wonder if getting more aggressive street brake pads would be overkill and give too much initial bite. Don't think I would like that. I'm still not planning to take my car to the track anyway.
Enjoy Bill's thoughts below.
Just thought I'd follow up after the test drive re: the brakes after some thinking. I really don't think there is anything to worry about, especially if you are comfortable with the level of braking effort required from the system. The only thing that stood out is how little initial "bite" the pads had, which is normally indicative of how track/race pads handle (lower initial bite than street pads, higher coefficient of friction as pads/rotors get up to operating temps). I have no idea what Porsche stuffs in their calipers from the factory now, but I do recall a 2004 911 I drove having more normal brake "bite" in line with other lightweight cars I've driven with big braking systems (S2000, Evo, STI, Corvette, etc.). Again, it wasn't bad, just different and very little initial bite... very strange for a street-oriented car.
I will say however, I LOVED the stiffness of the brake pedal. This indicates very good master cylinder hydraulics, fresh fluid, stiff lines, and a killer gravity bleed job (suction or pressure bleeds usually don't get the pedal that stiff). If the previous owner never did maintenance on the braking system, that is officially the stiffest pedal I've ever felt from a factory car. I would probably love it on the track because of how linear the pedal felt. You could probably keep getting additional braking out of the pedal all the way up to standing on it. Considering how stiff the pedal is, adding more aggressive street pads may be too much initial bite and you may get jerky braking behavior, which may or may not be your cup of tea.
When you DO replace your brakes (whenever that may be) here are two guidelines:
1) Get street pads for the street (duh). They have higher initial bite at low operating temperatures, which is important for "oh shit!" braking moments. This is important because on the street you aren't ever working the brakes enough to get up to proper operating temps required for track/race pads. They are also much more quiet than track/race compounds. Race cars sound like school buses when coming to a slow stop. :-) However, street pads are insufficient for track driving because they don't hold up to heat and their coefficient of friction drastically drops off once you get to high temperatures. It is a trade-off, but important to consider.
2) Drilled rotors provide little to no cost or performance benefits. They absorb less heat (less mass), wear quicker (easier to crack because of drilled holes), and are more expensive than blank rotors. They do, however, look good and that is why they are OEM on performance cars. You may not have a choice with factory Porsche equipment, but you can most likely find blanks by going through another generic parts supplier. I like Centric rotors as they are cheap, hold up very well to track conditions, and are made by Stoptech, which is in the same category braking equipment-wise as Brembo, Wilwood, Alcon, Performance Friction, AP Racing, etcetera. You'll find real race cars use two-piece slotted rotors, which are light weight and direct hot gasses away from the rotor face and pads. This gets very expensive and is totally unnecessary for the street (and often for the track, too, if you are on a budget and aren't sponsored by a team).
Just thought this might be a little helpful. Didn't mean to sound alarmist if I did last week, just haven't felt a pedal like that before.
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