Right now I have a flo-pro muffler and the 2.5" piping extended the rest of the way back, on the stock catback. Would It be worth upgrading to a catback? I'm currently running 2.8" pulley, and the other usual stuff.

 

I wonder this too. I have the mods in my sig and would love to know for sure if a full 2.5" cat-back would prove beneficial. IMO, the gains would be very minimal, maybe 4-7 whp.

 

Just get the restriction over the axle mandrel bent 2.5. Piping is piping, replace the resonator if you want, full 2.5.

 

CTI makes a 2.5" over the axel piece. Just get that and weld it to you're aftermarket muffler. Thats what i'm going to do.

 

I already have 2.5" over the axle into a flo-pro muffler. Would I see any gains at all from a catback or should I just keep the muffler?

 

Really, what would you be changing then besides the muffler and resonator?

 

Not really... I mean you would be getting rid of the OEM resonator that is supposedly 2.25". I changed my OEM resonator and honestly it appeared to be 2.5", but I already had it off so I had another welded in. Other than that, as long as your flo-pro muffler is 2.5", you're not changing anything by buying an aftermarket 2.5" cat-back.

Short answer, no you will not see a gain (VERY minimal if any) over your current set-up.

 

Ya guess I wouldn't really be changeing anything lol.

 

The inlet of the stock resonator is 2 1/16" i.d.

The resonator itself is 2.50".

People always forget or dont know about this bottle neck. If you dont want to purchase a full catback then def replace the 2.25" over axle piping, replace the resonator, and replace the muffler or get a stock SS/TC muffle if you want a stockish sound.