Right now I have Borla S-type axle backs, removed resonators and stock H-Pipe on my '14 GT.

Now I know that if I go with an offroad/catless x-pipe, I will need to get a tune. What about if I go catted with high flow cats? Is a tune necessary on that one?

Lastly, for anyone that has kept the cats, and just replaced the H with an X, is there really any noticeable sound difference? I know LOSING the cats will make a noticeable differnce.

 

X pipe definitely sounds different than the H, will be hard to Judge since you would be going catless or high flow.

Either way you would probably need a tune, any significant change in flow will need a tune.

 

Adding an after cat x pipe does make a big difference in sound. My GT500's were tame even with the resonator delete. With the x pipe it is louder and deeper at idle and sounds mean under throttle but is still quiet at cruise in the cabin and does not need a tune. IMO this combo is the best solution for a DD that you still want to have fun with.

 

I agree, I with a lot of what he^^ is saying, but go with the o/r X pipe if you can! That will have the biggest improvement on sound. The X will not be deeper than an H pipe though.

Are you looking for low end or high end? Because the X-pipe will help more at higher RPMs

Nick C.

 

It also depends on what you are trying to do as well. I have an h pipe (02 gt wish it was a newer on) and love the deeper tone plus I am trying to get as much torque out of it as I can. X pipes are more for top end and h is more for torque. But x or h the sound is bad *** you like either one

 

If i were exhaust i'd want to flow through an x rather then an h.. X pipes get you on avg. 4 hp more, and i lean towards power more so then sound. I love the angry sound of my exhaust with an offroad x and gt-500's.