wearing on the outside is unusual, except for hard driving, in side wear is more of a camber issue.

get an alignment done to find out

 

does your car pull when you let go of the wheel? if you have uneven wear, that is a sign of an alignment problem.

 

The front tires will wear some on the outside simply because they roll over to some degree from turning and agressive driving will speed up the wear. But, you may need a alignment. There are 3 factors in alignment. Camber, Caster, and Toe angle. If you have more wear than normal you could have more positive camber than normal, too much toe in, or combination.

Link is a good article that explains it all.
http://www.motor.com/MAGAZINE/Pdf/062002_05.pdf

 

Camber issues man. I was having that same problem too.

 

Take you car to your local NTB those guys are fawking pros. When i got my coil overs intalled my drop was close to 2.5" and i went to three different alignment shops to get a good job done, not one of them could do it becasue they told me the drop was so much that even with caster camber plates it did not allow for proper camber alignment. I was off by by 2 degrees on both sides...took it to ntb, i spoke to the guy who was going to be doing the work and i was like hey man do you think you're gonna be able to do it and he's like i don't see why not and i was like, well i've taken it to 3 places already and he was like..naah..don't worry i'll take care of it. Took about an hr and i was good to go.

NTB rules..