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?

 

[bushpilot]

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)

 

[Mark Craig]

2ManyToys,

The stock DP is 3.0 not 3.5 so the MBRP or AFE we sell is 1/2 inch larger and is also mandrel bent! Neither of these systems have ever had any bellhousing clearance issue that we have heard about either. Call us if you have some questions, and by the way the 4.0 down pipe provides 0 advantage and makes you bend the firewall and if you tow heavy and it might still hit when you have the engine torqued over!!

Mark @ DPPI

Mark @ DPPI