If you track your Boxster, or do a lot of long, high speed driving, a simple and relatively inexpensive upgrade you can make, in less than 30 minutes, to provide a bit more cooling air to your front brake rotors and calipers, is to swap out the stock factory brake cooling deflectors (Link Spoilers) for a set of the factory GT3 brake cooling deflectors.
The GT3 link spoilers have a good bit more surface area than the stock spoilers, and have two fins that protrude to further direct air towards the rotor and caliper. The factory part numbers for the GT3 link spoilers are: 997.341.483.92 and 997.341.484.92.
I purchased a pair of the factory GT3 link spoilers for $34.00 delivered from a seller on ebay. My Boxster is a 2001 'S' model. I believe the stock link spoilers are the same size on both the base and 'S' Boxster models. The factory part numbers of the stock link spoilers I removed were: 996.341.484.01 for the right side, and 996.341.483.01 for the left side.
I tackled the swap one side at a time. I removed the wheels to provide easier access to each lower control arm. I started on the left side. The removal of the stock link spoilers, and installation of the new link spoilers, takes place from the front side of each control arm. The stock link spoiler is held in place by two large interlocking plastic clips and several smaller plastic tabs that snap around the control arm's profile. With a small screwdriver, I pried the interlocking clip pieces as I squeezed them together until they unclipped. Once unclipped, you simply work the plastic clips over and off of the control arm.
Installation of the new GT3 link spoilers is just the opposite of the removal of the stock parts. There are a pair of tabs in the middle of the link spoiler that fit in between two small ribs on both sides of the aluminum control arm. It's important to position these tabs inside the two small ribs to position the link spoiler properly. Once you have the new link spoiler in position, simply clip the two large interlocking plastic clips together, and you're ready to tackle the other side.
Once both of the GT3 link spoilers were attached, and the car lowered, I took a look to see how much further the GT3 link spoilers protruded down towards the pavement. On my car, while the GT3 link spoilers do have more surface area that hang lower than the stock link spoilers, it's not all that much to have to worry about.
While I've not experienced issues with my brakes fading from prolonged high speed track work yet, we have a drivers ed event coming up at the end of the month.