Custom Catback ?

[gqdabien]

I will be getting two mufflers universal w/ 4.5 inch tip. i wanted to know if its a smart idea for a shop to universal catback 2.5 inches which does a Y shape to split into two separate mufflers on my I4. I know I4 will lose power on dual mufflers but should i get the catback done anyways?

Also if i'm planning to do catbck should i do the headers w/ cat first or this first? Thanks.

[djprefix]

It doesn't really matter what you do first. And it you'll gain hp with the dual mufflers but only on top end, you'll lose low end torque. And if you only want the mufflers and exhaust for the sound then it shouldn't matter if you lose performance. But if you're doing it for performance; as you make your engine more powerful the exhaust will gain you more hp, on a stock car it'll have you lose some low end torque though.