60-70mm is aprox. 2.358-2.751in (like the GReddy Evo)
45-60mm is approx. 1.7685-2.358in (like the Apex'i WS if I'm correct)
As stated earlier, most turbo cars run 3" aftermarket catback exhaust piping (friend has Invidia exhaust on his WRX with the slanted pipe exit and everything, very nice). Like anekin007 said, get a header upgrade as well to really feel the results.
As far as your exhaust getting loud or being loud... over time the exhaust will become louder as the packing/insulation in the muffler wears over time that plus it helps to have a 5sp. and not an Automatic slush-box to hear the exhaust more. A girl I know doesn't like her exhaust (GReddy Evo) because she feels it isn't loud enough, but she's got an automatic plus the exhaust is brand new (put it on not even a month ago) so...
45-60mm is approx. 1.7685-2.358in (like the Apex'i WS if I'm correct)
As stated earlier, most turbo cars run 3" aftermarket catback exhaust piping (friend has Invidia exhaust on his WRX with the slanted pipe exit and everything, very nice). Like anekin007 said, get a header upgrade as well to really feel the results.
As far as your exhaust getting loud or being loud... over time the exhaust will become louder as the packing/insulation in the muffler wears over time that plus it helps to have a 5sp. and not an Automatic slush-box to hear the exhaust more. A girl I know doesn't like her exhaust (GReddy Evo) because she feels it isn't loud enough, but she's got an automatic plus the exhaust is brand new (put it on not even a month ago) so...