MY friend and I just installed High Output alternators in our Suby's and were running a few tests with a multimeter and a voltmeter on my radar detector(8500). My friend has an 04 FXT auto and when he is parked his audio system runs fine, but when he put it in drive, his system will cut out after a few bass hits. He even has the 15 farad Alumapro C.A.P. We measured the voltage and when he is in park it averages 14~14.3 volts with the system on and everything. But when he puts his car in drive, the voltage drops by an entire volt to 13`13.3 volts. It then slowly bounces voltage with the music until it drops below 12 volts and then cuts out at the amp. The amp has a protection circuit that causes it to cut out. What could cause the voltage to drop so much by putting it into drive. This happens even on the highway, so it is not an RPM related problem.
I drive a stick WRX and it does the same thing to a lesser degree from neutral into a gear, and overall has a lower average voltage.
Our alternators should be identical, and have the same output, so there must be some other players in the voltage stability. Hopefully someone can give me some insight as to what the heck is going on.