With so few S8’s sold I just thought I’d post this up here. I know this is in my build thread on the S6 section and in the performance brake rotor post but if someone was like me doing brakes and didn’t know off hand that you need a computer to help you open the rear calipers this thread is here for them.
This week we drop another 10lbs off the rolling weight of the car with the JHM rear rotors and I walk quickly through what you’re going to need to do with vag com to be able to get the rear breaks off.
Yes, you read that right. You can’t do rear breaks on these cars without the help of the computer. So, when you’re doing brakes keep that in mind. You’re in good hands here though, I post at the bottom on what you’re going to have to do to open the rear brakes.
Now on to the thread.
I did the front brakes and dropped over 30lbs between the two of them. Each side I was able to drop 15lbs with the JHM LW rotors.
With that big impact, I thought it would be time to drop a little weight from the rear rotors. Again using the JHM rear rotors.
These not only look great but they function better than the OEM units and they weigh 5lbs less each.
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With the JHM rear rotors, you’re knocking off another 5lbs a side. For rear rotors, that’s a lot of weight. You normally don’t see that kind of weight reduction in rear rotors. The front brakes do the majority of the work so the rear brakes don’t need to be as big. Still, it’s a good area to shave weight when you can.
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With all this weight savings I actually saved a ton of money. Usually to get these kinds of weight savings you have to get light weight rims. Since the S8 comes with 20" rims stock. It’s kinda hard to find nice light weight 20" sport rims.
Oh, and if you’ve ever wondered how much the OEM S8 rims and tires weigh.
http://audirevolution.net/addons/albums/images/242843170.jpg
That’s a lot of weight for rims and tires.
Now for the technical part of the post. Most of you might not know but you can’t just jump onto the rear rotors like you can the fronts. The rear rotors with the electronic parking break require the use of a computer to unlock and open the rear brake caliper.
If you’re a DIY’er 90% of the brake job is going to be the same the rear brakes come off easy without much fuss but when you need to open the caliper you’re going to need a computer. If you have a vag com I’ll show you what you have to do.
EASY STEP 1
Open vag com and select the “SELECT Control Module” option
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STEP 2
Select option #53 - Parking Brake
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STEP 3
With the Parking Brake controller open click on the - 04 Basic Settings
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STEP 4
In Basic Settings open the drop down menu and click on Open Rear Parking Brake
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STEP 5
You might have to still help open the piston manually. Clicking on Open Rear Parking Brake doesn’t necessarily open the piston all the way. You might have to open it to the specific spot you need to place on the pads. Now is when you would push back the piston on the caliper as far as you need and put in the pads. After the pads are on and the caliper is back on and in its place. You’re ready for the next step
STEP 6
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That will get you all set. Some people like to do the Parking Brake Function test. I never found a need for it. That’s there if you have an issue and you’re checking the function of the system.
This walkthrough works for most cars with rear parking brake systems.
Now with all the weight lost from the JHM Rotors, you’re car will be transformed into a lighter fighter. All in all, it’s a mod worth doing. The rear rotors don’t get changed that often so this mod should last you years and years and years before you’re going to even need to think about replcement of the rings.