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Full Version: Are you satisfied with the brake system?
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Hi all,



As I wrote in the 'Introduction (Hello from Japan)', I live in Tokyo, Japan and I purchased my 968CS this May. So far I've driven the 968 around 1,500Km (roughly 1,000 miles).



My impressions are engine and mission are quite healthy but suspension and brake system should have some problems. So I asked Mr. Tatsuji Kuranuki, president of "Met's Speed', to check my 968 if there are something malfunctioning. Met' Speed is not a huge maintenance factory, but somewhat famous as an excellent 968 maintainer.



Discussions with him regarding air cleaner (mine has a K&N), brakes and suspensions were quite interesting, but this time I like to focus on the brake system.



My 968 CS does not have M030 sports chassis. In my understandings, this means the car has the same suspension and brake systems as normal 968 (black caliper).



Mr. Kuranuki drove my 968 and said the brake was OK, but he also got at the brake system itself were not so powerful enough. I heard some owners changed the brakes to M030's, or more radically to 964 Turbo's which must be astronomically expensive.



Since my brakes were diagnosed to be normal, I don't plan to change it immediately but I am a bit frustrated with it.



How do you feel and think abut this brake system?



Regards,

JasperTomo
most people, unless they are tracking the car, feel that the brakes of the 968 are stellar, and one of the best features of the car.



i suspect that you likely have glazed pads/rotors, inferior pads, or a combination of both.
I agree that stock 968 brakes are very good. That said I did replace my brake lines with Stainless Steel (Clutch hose at the same time) and added cross drilled rotors (as much for looks as function). Pads make a very big difference, many here are using Porterfield. I am very careful to fully change brake fluid every 2 years (about 5,000 miles for me).



Regards,



Jay
Thanks for your comments. I will keep investigating the possibilities of improving my brakes. No matter my brake is normal or not, I like to have more stopping power for sports driving.



Regards,

JasperTomo
I just changed to cobalt brake pads and was very pleased with their performance at the track. Although I don't do a lot of street driving with the car , I did drive back from Watkins Glen and down and back to Provost and continued to be happy with them.
I had to change out my pads to run effectively at the track, but am pleased with the braking on both street and track. I am running Hawk HT-10s for the track and Porterfield R-4Ses on the street. I tried the Porterfields on the track and was just giving away WAY too much braking torque.



I'm guessing your pads aren't up to stuff if you're not getting the braking force you want.
I just had the front brakes redone. Used Zimmerman rotors and Pagid Orange brake pads. Definetly as surer feel up front which get the most wear and tear.Not a fan of cross drilled rotors as I've seen too many develop cracks emanting from the holes.
i have NEVER needed more brakes, even on the track. but, i drive differently that most, and don't use the brakes much anyway. i learned to drive a "momentum car", and in one of those, you don't really use the brakes.



i still think that if this is on the street, no matter how hard it is driven, the problem is likely not the brake system, but rather the condition of the pads and rotors themselves. the white car has OEM pads on it, but they have been there for years. they are a bit glazed, and consequently don't stop as well as they could. ds968's car has ceramic pads on there that are glazed. that car almost scares me.



this is a far more frequent problem than people realize. they look at the thickness of the pads, and look for grooves in the rotors, and go on about their day. that's only half the story though.



often people don't know how to properly break in and bed their pads. this leads to immediate glazing.



often people just do a "pad slap" and don't address the rotors. this often leads to glazing, especially if they changed pad type without changing the rotors. you can't do that. pads and rotors "bond" to each other. at a bare minimum you have to surface your rotors EVERY time you change pads. that may not do it though. it is not at all uncommon that once a rotor has broken in to a particular pad, it cannot be switched to another pad, regardless of any surfacing you do. the change in the rotor is a molecular one, and goes all the way through.
Many good points made here, and I don't have a whole lot to add, but I'd like to point something out someting I read a few years ago that has stuck with me, because it was so contrary to my prior belief. Many people say they can detect "huge" differences in their car's braking performance as a result of changes to parts of their brake system hardware, such as lines, brake fluid, and pads, that don't impact the actual swept area. However, a few years ago, Car and Driver magazine did a very thorough test checking the impact of these changes, and emphatically found that it just ain't so. Fluid and lines had zero effect, and the differences in actual stopping distances among the different pads was even quite small. Their conclusion was that the impact of these items is largely placebo, and the only thing that has a significant impact on measurable braking performance is the ability to convert kinetic engergy into heat, which is dominated by swept area. Yes, at extreme track conditions, pad type definitely makes a difference, but for the way most people drive their cars, their conclusion was that investing in expensive brake fluid, stainless steel lines, and high dollar pads is a waste of money.



But I do agree with Flash that something that compromises the interaction between the pads and rotors, such as glazing, can significantly impact braking performance (this wasn't something C & D evaluated in their test).
you have to be careful about tests like these. if they didn't do a heat saturation test, then they really aren't being fair. that's where premium pads show benefits. it isn't in first stop stopping distance. it's in the100th repeated stop.



that being said, for the average driver, they are right.



it's all about heat. if you drive the car hard enough, you can enjoy the benefits of better pads. if you just sit in stop and go traffic, or drive it to the grocery store, you won't.
Agreed - that's what I meant by specific pads offering advantages on track cars. In fact, Grassroots Motorsports recently ran a test on different racing pads, and found small but measurable differences between them that was manifested in lap times. It's been awhile since I read the C & D test, but I'm sure the emphasis was on street driving, but I'm also sure they did a fade test. I was just struck by how little difference anything made, short of installation of larger rotors and pads.
odd. i did a test of sorts when i changed my pads, rotors, lines and fluid. one before and one after. i shortened my cold braking distance by over 10 feet. when i changed the brake bias valve to one with more rear bias, i dropped more. my figures won't equate to anybody else's car, due to my tires, weight distribution, suspension, etc, but things did add up to shorter distances.
Just changed rotors and pads from Zimmerman cross-drilled all around and Pagid pads (OE version) to solid rotors (Sebro) and Hawk pads all around. Followed the instructions to "bed" them in. Result is braking capability that is

nowhere near what I used to have and also nowhere near Pagids with solid rotors all around, which was how the car was set up when I bought it. I always loved the braking capability of the 968 and found it more than

able to perform.



I had used up the Zimmerman rotors and they could not be resurfaced, which was the reason for the change. There was some warpage in the driver's front rotor. I wonder if I should get Pagid pads back on the new rotors or if I should resurface them, with only about 100 miles on them.

A bit frustrating. Thoughts, anyone? Thanks.