Going with my new engine build, I am going with a 160 amp motorcraft alternator. Here is the system that is going in. Alpine IVA-w910 Alpine PDX-F4 100x4 (rms) Alpine PDX-17REF JL 12v3w3 JL JX500/1 (rms) Using a calculator, I am figuring somewhere between 80-88 amps draw. I am thinking it is going to be close, but I dont want the flickering light syndrome. Will this be enough....or should I start looking for a bigger alternator.