The Porsche Boxster has fantastic brakes when they are in good condition, correctly installed and maintained.
However one complaint of the Boxster braking system is that the brake disks wear out reasonably quickly. But this is to be expected from a high performance car. During the design of Boxster brakes, Porsche would have had a trade off available to them with a sliding scale where they could choose between the importance of braking efficiency versus brake pad/disk wear. I personally am happy that they made the choice of preferring the highest performance of the brakes rather than wear resistance. One day on a dark night when you have to perform an emergency stop you too may be happy they made this choice.
One interesting point about Boxster brakes is that it has been mentioned by several Porsche main dealer and independent technicians that the Boxster brakes wear out more quickly on cars which are driven less frequently. Initially I thought this was a crazy situation until it was explained that surface rust forming on the disk will be removed when the car is next used, and this cycling between rusting and the rust being scrubbed away causes rapid brake disk wear. My advice is to use your Boxster on a regular basis.
The Boxster 2.5 and 2.7 from 1997 to the 2008 model years share exactly the same brake disks, pads and calipers. Sporting 298mm diameter front vented disks with a thickness of 24mm. On the rear the disks are 292mm diameter vented disks with a thickness of 20mm. The diameter disks as a Porsche 964 (1989 - 1994 911)
The Boxster S 3.2 from 2000 to 2008 model years has larger disks. 318mm diameter vented front disks with a thickness of 28mm and 299mm diameter rear vented disks with a thickness of 24 mm. However as well as being larger the Boxster S disks are also cross drilled and on the front they are handed (different design of venting and drilling on the left and right sides. The front disks are the same parts ask used on the 996 3.4 and 3.6 (even the C4S) and the same as the non S 997 front disks!
The following is a table showing the part numbers and specifications of the Porsche Boxster brake disks used on various models.
You will notice that the 2.5 and 2.7 Porsche Boxster does not sport cross drilled disks. Originally the Boxster 2.5 which evolved into the Boxster 2.7 was intended to have the same disks, yet cross drilled and many of the original press cars were installed with these brake disks.
When I talked to my Porsche specialist about the original brake disk design he called the manufacturer of brake disks to Porsche and talked to them about the issue, who confirmed that the original 60 Boxsters had cross drilled brake disks. It also turned out that they can indeed still manufacture these disks. My specialist now keeps these brake disks in stock. However whenever he runs out earlier than expected, there can be up to a 4 week wait for another batch as they are especially made. Apparently he is the only customer for them. If you would like to obtain some for your car, you should contact them direct via their web sitewww.jmgarage.com
The Boxster and Boxster S use different front brake pads but the same rear brake pads as you can see from the application chart bellow.
Some interesting rules to follow when replacing your own brake disks or pads....
Always use new pads when fitting new brake disks.
Disks should always be replaced in pairs across an axle.
Pads should always be replaced in pairs across an axle.
When installing disks or pads, always replace all bolts, set screws, pins, dampening disks, clips and wear sensors with NEW items.
Another common problem with Boxsters is that during caliper removal and reinstallation its sometimes found that the threads of the aluminium hub crumble as the caliper bolt is removed. This can easily and permanently be repaired by machining the hub to accept a steel thread insert.
Send comments and ideas to web at piperboxster.com