Right after the annoying drip on your leg from a leaky top the number 2 most annoying thing about cabbys is the ridiculous electrical charging system. Coupled with a voltmeter that you learn to ignore you're left wondering if your battery is ever charged properly. And since you have a Bosch alternator the answer is, probably not.
A 12volt lead-acid battery needs at least 13.6 volts to charge properly. Your charging system is giving it that and probably no more if you add in the usual voltage losses from bad connections and grounds. If your car was a Ford you'd have a charging system putting out 14-14.5 volts so you'd have some headroom.
So let's pump up the volume shall we?
Remove your regulator (easy, only two screws) . Now examine it and see the one lead that goes under the mounting /grounding screws. Break it off. Now take a diode and place as shown. Solder it to the terminal after scraping/filing the metal clean.
What we are doing is adding a voltage reference for the regulator that is .5 volts different than before. So our 14 volt regulator is now a 14.5 volt regulator. And if you clean up all your grounds you'll get every drop of that. It's really neat watching your voltmeter swing over into what used to be virgin territory on the dial.
I've seen this documented elsewhere on the vortex but thought it was about time we talked about it here.
Make sure your diodes are at least of this level 200v / 3A .