I have 2 12s running at 2000 watts rms, i have 0 gauge running to the amp, 0 gauge on the big 3 upgrade and a optima redtop battery and am still experiencing lights dimming when the bass hits. But i can't seem to find any high output alternators for the 1st gen rl's, is it possible to find another high output alternator for a similar car with the same pully size and get a bracket custom made or something along those lines?

 

Remembering Ohms Law which is: Amps x Volts = Watts. Or in your case, 2000 watts divided by 13.5 volts = 150 amps. There are a few variables here. Keep in mind that you have other electrical needs of the vehicle, lights, A/C, etc. I believe your alternator has an output of 130 amps, and with your stereo running at max, you will obviously start draining the battery pretty quick. Here is a thread on this site about the same problem you are having:

https://acurazine.com/forums/3g-tl-audio-bluetooth-electronics-navigation-94/high-output-alternator-704021/

If you are intent in just finding a high output alternator, I would suggest you check out www.powerbastards.com. They make a universal fit alternator that has a full output of 220+ amps. That should take care of your problem. They run about $350 and up depending on the pulley and if you want it chromed or some other color.