'06 Exhaust: Turbo- or Cat-back

[2ManyToys]

Okay, I'm doin' my homework for my new '07. If most of the after-market, including MBRP, are providing 3.5" down pipes as part of their turbo-back systems (which is the same size as OEM) why go full system? There are true 4" systems out there (HOG, ATS), but I'm told they require modifications to the firewall for clearance. If you use MBRP's "test pipe", it's 3.5" as well (I called them). I haven't actually looked at an '06 OEM pipe, is it "crushed" or "dimpled" for clearance? What am I missin' here?
And the new one's another "twin-stick", so some manufacturers don't clear the bell housing.
Who's got what, and how did it fit?

 

[powerboatr]

read here

and 7 of the views are mine, I am having dserver connections issues today-mad

 

[oi8228oi]

i say goo for the hog but that might be cause i have a hog....

 

[bushpilot]

agree go for it all...youll only wonder "what if"... when you dont
--------
true 4" systems will FORCE you to modify the firewall (read: DENT)
in order to gain proper clearance....and honestly i dont want a hot
down pipe traveling that close to my firewall (let alone having any
chance of vibrating or rubbing)...

and im NOT comfortable w/ DENTING in my firewall.

the MBRP stuff fits...plain and simple AND you can bolt in/out
the soot trap if you need (for what ever reason)....the mbrp is
mandrel bent...the factory tubes are not.

even if you go w/ a cat back exhaust you could STILL bolt in/out
the test pipe (ive PERSONALLY done it w/ a friends cat back NON-MBRP
system)