bro he's also adding air intake to it,plugs aswell,there's a guy who lives two streets away from my place he's having the setup i told and trust me his margalla runs runs and runs,
i personaly kept margala for 5 years it has a brilliant pickup and handeling+road grip.it sucks air in real hard and when u add performance intake it will suck more,though most of guys say that it should 2" 4 margalla am not saying that they'r wrong but 2.5" creats big sound aswell other wise yes if u go with 2'' piping its equally good aswell,