charging problems

ok, I have an 89 ford mustang mods are 347 Eagle short block, forged crank and pistions,Tfs heads 185cc, Holley systemax intake, trick flow stg 1 cam, 4.10 gears, T5 tranny, 32lb injectors, Saleen rear axle, Griffin aluminuim radiator, A/C eliminator, 70mm throttle body, king cobra cluth, BBK longtube headers and x pipe, flow master exhaust 40series mufflers.
It also has a optima battery red top and a 130 amp alternator, I made sure it was hooked up right and is also ran through a fuse. If I run it everyday, it will be charged fine, no problems starting or anything. But if I let it sit for 3 days or more, the bettery will be completly drained!! Any ideas?? Could the alternator be to small?? I dont have a stero system or anything like that either. nothing extra is hooked up electronicly!
 
It sounds like you have a drain. Start pulling fuses with a test light on the end of the negative terminal. Touch the test light to the battery as you pull fuses. It helps to have a friend pull while you watch or vice versa.LOL You'll find out which fuse circuit its on. What is your battery voltage at dle? My coupe is running at 13.7-14.0v(stock pulleys) and the battery is in the trunk.

I have this same problem on my vert. I pull the fuse if i know the car is going to sit to long. I'm pretty sure the drain is from the people that installed the alarm, something is screwed up because its on the power windows and locks circuit. I also didn't install the 3g alt correctly on this car. I basically connected the two orange and black wires and was done and didn't upgrade the ground when i installed the battery to the back. It produces 12.9v or so at idle(with U/D's) Now that the coupe is done (well for the most part) and is my DD, I will devote more time to the vert.
 
Check for a glovebox, vanity or trunk light that is staying on.

To test for parasitic draw, be sure all of the accessories and lights (interior and underhood too) are off. Disconnect the negative battery cable and put your meter in-series between the disconnect cable and battery post. With the meter set to measure current-draw, you'll probably see 100+ mA on the meter. Do the fuse pulling [as noted above] till the reading drops. Then dissect that particular circuit further till you find the source of the draw.

Most meters have about a 10 amp capacity ammeter. Don't power anything up or you can blow the meter's fuse or hurt the meter.

Good luck.