Intake/exhaust/reflash question

mpp9

I've seen dynos from a stock m3 and a modded 370z and they're scarily close in the power curves relative to how flat the torque is from 3k to 7k rpm and peak hp around 8k rpm. They couldn't feel or sound any more different but thats where the truck like sounding engine in the Z is trumped by the effortless feel and tech of the m3's v8 which then justifies the m's hefty price tag along with it's insane handling in such a heavy car. The guy owns the m3 also has a z4m and a maserati coupe so I just think it'd be funny to trump them all with a couple thousand in mods with a n/a car vs. an evo or sti.