Well, first of all, i'm no electrical master. But i do know that it depends on what ampere your alternator is putting out and at what rpm. If you plan on sitting in your driveway bumbing all night long, then what you want is an alternator that puts out the most amps at a low rpm, like at idle. If you plan on getting some huge system, i definately reccomend getting a new alternator. Try to find out if there was ever a police car of whatever car you have. If there was, get a police alternator. Police alternators are made to make the most power at idle, because when they stop to get out of the car and do whatever, they have their lights on, all the flashers, maybe the siren, whatever, they're made to put out a lot of amp's at a low rpm, and that's what you want, so find a police alternator. If not, find a better one than the stock, because stock anything *****. Next, I have an 88 mustang that has an 85 amp alternator and some stock quality battery. I'm running a 425W amp, and with it all the way up, sometimes i can stall the car because it runs out of juice, and i don't have all the fancy lights and stuff. So, I suggest that you either A. Get a capacitor or B. get a better alternator. (of course, that's just my oppinion) Also, one more note, neon lights don't take much power to use, so you might be fine with what you have, just try your setup, and if it doesn't work, than do something about it then.