sr20 blacktop start up issues

[bentmode360]

my blacktop starts up but it takes a good 2 to 3 cranks to start it up but everytime i would start it the negitive on the alternator would burn up.
-so i got the starter tested. its still works
-changed the negitive on the on the alternator to a heavier gauge.
-charged the battery
and it still does the same thing but its not burning the negitive anymore.

so i was wondering if anybody has had this same problem if they could give me an idea on what it could be because i just want my car to start up fine.

thanks