There is. Firt you have to check and set the "venting clearance" on the rear brakes. It's a bit complex, but not too difficult unless something strips or otherwise goes wrong. Once that's done, you can set the cable length with the threaded adjustment near the left side of the firewall, underneath the car.
Here's a link to the procedure:
http://www.914world.com/bbs2/index.php?showtopic=90625I'm gonna add a couple of thoughts: First, you want to be sure the rotor is clamped flat to the hub. Running on a couple of lug blots meant for steel wheels is a good way to do this. Be sure they're opposite each other, and not excessively tight. Next, I use a long feeler gauge and leave it in place while I'm turning the disc to check for high spots. I let it extend clear past the pad, inserting it from the top, and I turn the rotor so it pulls the feller gauge down, away from my fingers. By holding it with my fingertips, I can judge the drag and identify whether the clearance is good. I always use .004", as that's what they told us at Porsche school, many years ago. Good luck!
The Cap'n