I would hate to say it but...I have had the exact same problem with my SVT for about 2 years now. The battery light comes on on high rps. before it even stayed on and I had to turnd the motor off and restart it, so I can get my alternator running again. Here is what I found.
1) it is not the battery (tried 3 new ones)
2) it is not the battery terminal cables (checked all isolations, and fixed the cracked once)
3) it is not the alternator (replaced it twice and now I have a new, not rebuilt, Bosch, 130amps if I am not mistaken
4) it is not the cerpentine (accessory) belt, changed that last month, so I know it is not slipping or loose...
sooo, the problem started after my alternator died on my 2 years ago. It was replaced at PepBoys, and ever since I pick the car up it has been doing it. So, I found that in the alternator there are two plugs going in. One is big (with 2-3 wires coming out of it) and the other one is small squarish white/gray with a single wire. The mechanics that changed my alternator broke that plug and it was kinda loose in there (the plug should snap on, and lock itself in position when in good condition). So I pushed it in, and the problem was fixed for a few months...I got a new pug from a junk yeard, cut the old one out and...now it is still doing it. Maybe my wire connection is not good. I don't know, but PLEASE PLEASE PLEASE, let me know if you find a definate fix for that. and DO check your plug and see if it is tight in there.
keep me up to date!!!
