but not much performance ! u will feel a change, but not 20 30 hp gains if u understand what i mean ! ur car will have better flow and will have no restriction in flow ! if u need more performance and if ur installing an orignal exhaust for performance not for sound then u need wide and polished headers(exhaust manifold) , 2 inch and 18 gauge or more good quality exhaust pipe (depending on the engine) with no welds if u want it in pieces then make brackets in them welds restricts flow , middle resonator (preferably orignal one or u can make custom) , and a orignal jasma approved or other good brand exhaust ! the main difference between orignal and china or taiwan or custom made pakistani exhaust is the quality and gauge of the resonator used in it ! orignal ones are polished they have the perforations in sequence and the gauge is very wide around 12 gauge ! for example i owned a FGK jasma exhaust previously it had a very thick resonator ! by which its sound was very smooth and heavy ! and it did a very good gain in performance ! now i have waydo TRD exhaust and TRD middle resonator when i installed it, the flow was good engine is reving very smoothly ! im sure this would help 
