I've had my 2012 mustang v6 for about 4 months now. I love everything about it, except for the exhaust. Previous owner had stock exhaust up to the borla atak axle backs. I love the raspy note it has, but I want something louder and deeper. So I ordered a set of bbk long tubes yesterday and they'll be in tomorrow evening! Really excited. A friend of mine owns a 2011 camaro ss and installed headers on his without installing a new mid pipe and brought to my attention we could just cut the stock x pipe and weld/clamp the headers to it. In the process removing the cats. Every forum I've read has insisted on installing a matching mid pipe with long tubes. I wanted to see if anyone here has successfully done this.

Also, I have 3.31 gears. I've read that the sixers with 2.73 gears really suffer from the lack of back pressure caused by opening up the exhaust with long tubes. Do y'all think I'll be alright with 3.31s or think I should jump up to maybe 4.10s?

Mods so far:
Airaid intake
Borla Atak axleback
20" ZR downforce concave staggered
275 rear 255 front
BBK LT headers
Smoked lense kit and fender hash marks from American Muscle.

Here in a few weeks I'm picking up a tune from MPT and plan on getting the ghost cam tune as well.

Also plan on lowering it a bit. Maybe an 1"-1.5"
Here's some pictures.

 

3.31's are fine, that's what i had but changed to 3.73. If your doing away with your catts, it would be easier to buy a 'off road' matching x pipe. Long tubes are very easy to put on yourself and your going to feel a lot of extra power on your first drive. I ran my long tubes for around a month before i had my tune changed, with no problems. When i got my new tune i couldn't feel any difference between the two. Nice looking Mustang

 

Hey David! Thanks for the response!

I Installed them yesterday! Ended up fabbing my stock mid pipe, removed the cats , hollowed the resonators and welding it up to the headers. So there's definitely a gain at the higher end and a small loss in the low end.

I'm definitely running a bit rich on fuel. At first I was just thinking it was because I was pedal happy, but I've been driving around like a granny and still only getting 12-13 mpg city. I'm guessing a tune will fix that for me. It's extremely loud. Yet surprisingly there's not much drone.

Here in a few weeks I'm getting a tune so hopefully that solves the gas mileage issue and brings more power

 

Oh and I wanted to add that I have the 02 extensions for the forward o2 sensors connected, the backward o2 sensors are disconnected. I haven't received an engine code yet, maybe that's what's causing the crappy mpg. I don't know.

 

Here is my MPT ghost cam tune

 

When i installed my long tubes, i was running a $200 Evolution Performance (Jon Lund) tune. I ordered a new MPT tune for my newly installed headers. I got a 02 sensor code and called MPT about it. They sent me a new (free) tune with the rear 02 sensors turned off and it fixed the problem . A few months later i ordered a new Evolution Performance tune and as far as i know all the 02 sensors are on with that tune

The MPT tune pulls a little harder than the Evolution Performance tune but the Evolution Performance tune has better and more refined shifting on my 'automatic transmission'.

 

Love mine...and +1 on a very easy install. Remarkably so actually.

Those disconnected O2 sensors are probably not helping the MPG, so hooking those up would be wise. They're also important for closed-loop control, which can be good for power too.

 

I'm getting a tune very soon. I'll see how the gas mileage gets, If that doesn't work I'll end up getting a catted x pipe. It's so loud lol. Anything over 3k rpm is ridiculous. Yet if I'm around 1800-2000 there's almost zero cabin noise.

 

Mines a 6 speed! So I'm gonna go with MPT. I'm really excited for the ghost cam. Your mustang sounds badass David!

 

Thanks . You don't realize how much the factory catts cut down on the sound until you remove them. Thats why i bought the catted x pipe. It has very small catts but help on cutting down on the sound. My long tubes and catted x pipe made my Magnaflow street series axle backs around 1/3rd louder. I don't have any drone at any rpm. I have some Magnaflow Competition (straight pipes) axle backs i put on for a week or two a year, just for a change. Talk about drone and loud as hell . Fun for a little while but i wouldn't want to run them all the time .