1badstang, i gots the same problem.......
its a combo of things for me.
1. battery
2. orginal wires
3. fuel pump is on her last leg.....
4. too much stereo
I can ussually get around things by starting the car once a day atleast and letting her idle for a few minutes. I did a "quick" tune up by cleaning my wires and what not when i did my intake and that seemed to help. When i changed the battery problem was solved for a bit, but because of winter and the car sitting for weeks at a time that solution didn't last long.
as for putting in 900rms watts.........get a capaciter :lol my system is the biggest cause to my hard start up.