okay, so my alternator is just a couple months old, should be good its reman by a quality shop. has no problem running the car with a dead battery/no battery, but my battery will die after about 4-5 days of driving 20mins at night. from what i can tell it is hokked up correctly (just finished my 2nd motor swap so it was off and disconnected for a bit, but its just two wires, how can i go wrong?) ideas? one of the wires off the alternator has a black lump in the wire, fuse maybe?

.
.

How old is the battery? It's possible that your alternator isn't charging "enough". Believe it or not, Sears is able to do a full battery/charging system check (I know, I work there in Automotive) that's fairly reliable. Also, thing about batteries. They can be good for a year, then go to crap for no reason. Also, if they sit with no charge for a while, they tend to go bad. Like a car, they need to be used to stay in good shape.

could be a bad alt, i got 2 bad ones from nappa, finally went to autozone and got a good one, have them test it before you walk out the door with it