don't go near a single.

 

i dont think your audi woulkd let you do a single...it might get mad at you......go with the dual tip

 

dual with out second thoughts.

 

thats wat i was hopin to here from u guys cause from the beginin i wanted the dual but then when a bunch of ppl started sayin the single would look better and would be louder i had to get the pros(you guys) opinion on the matter and im gettin it done tomorrow after school so thanks for all the help

 

here is what 3.5 or 4" looks like on a silver A4