Does a resonator on a b-pipe hurt airflow at all? Are there any performance gains at all with a b-pipe without res? (assuming the rest of the exhaust is free flow as well)

 

yes, resonator hurts flow, but on our cars not enough to notice any real gains. we're talking 1/4 to 1/2 hp gains, the main reason people get rid of the resonator is for sound purposes, same as with the rest of the exhaust.

Unless you're boosted or juiced, then its a different ballgame, but i don't think you'd ask this if you were modded like that...