Chevrolet Repair: vehicle voltage, camaro z 28, altenator

Question
95 Camaro Z-28.  The altenator charges fine when the car is at idol or when you drive it at low rpms.  When I give it more than a little gas the voltage drasticly drops.  The alternator was replaced a month ago with 140amp altenator.  It worked fine for about a month, but now the voltage is dropping.  I had the altenator tested yesterday and they said it was good.  I'm in the military and stationed in England and no one on the local economy seems to know anything about my car.  Any assistance would greatly be appreciated.  Thanks  

Answer
Hi Jesse, The first thing you to do is have the belt tensioner checked to make sure it has enough tension on the belt. I have seen belts that were worn to the point that the tensioner couldn't apply enough pressure to keep the alternator spinning fast and the voltage drops. This will happen at higher rpm's only. Also make sure that the belt is routed correctly on all pulleys.

Mark