atm i have a 2inch exhaust from the catback.
my question is if i install some 4-1 extractors (or 4-2-1) and a 2inch full exhaust will the rpm range increase?!?
at this time, i can rev the engine to about 6k no problems but anywhere beyond doesnt create anymore power at all and redline is about 5600
and if so, how much would this set me back? keeping in mind i only need the exhaust to go to the cat.