Does anybody have the Magnaflow 4" that replaces the turbo down pipe as well? I'm curious how well the turbo down pipe fits and what the overall fit and finish is otherwise. Is it a louvered or a perforated core muffler?

Thanks!!!!

I would be surprised if there was an actual downpipe that connected to the turbo - there is not a system that has been designed yet that encorporates this piece. Always from the factory turbo downpipe back.

Downpipe-Back: Bolts up to the OEM downpipe flange, yielding substantial gains in horsepower, torque, fuel economy and a lower EGT (exhaust gas temperature).

Turbo-Back: Replaces the flattened OEM downpipe with a stepped mandrel-bent down pipe and OEM style flange that bolts to the back half of the system. Use when a few engine modifications are planned.

That is a copy/paste off of the website selling it. I'm a little skeptical as well, which is why I am asking if anybody actually has the kit.:confused:

not yet.. no true downpipe.. the pipe all the exhaust places call the "down pipe" is actually the front pipe. The actual down pipe on the turbo is so close to the firewall that its almost flattened..no way to upgrade this peice at present time.

Briano, I tend to agree with you, but reading the description it does sound like they are replacing that flattened pipe?????

It does definately sound as such. If it doesn't replace the factory downpipe that bolts to the turbo it is awfully misleading print imho.

I just talked to a tech at Magnaflow, their system bolts to the factory downpipe which comes off the turbo itself. I told him his advertising seemed a little false to me, didn't have much to say. Went on to say that the new LLY's will trip a code if they don't have enough back pressure, maybe that's why they don't replace that part..... Are you guys that removed the Cat with a full system tripping codes?

I Have The Magnaflow 4" 'turbo-back' System On My 05. It Does Set Codes Without The Cat And Ses Light On Cal Trucks But The Finger Stick Cured This Problem. It Is Similar To Everyone Else's 'turbo-back' Systems Starts The 4" Pipe At The Factory Clamp At Lower Pass Side Of Engine. System Fits Perfect And Sounds Great. Nice Deep Rumble Outside, Just Slightly Louder Inside.

Pwdr Extreme,

The Magnaflow doesn't nor does anyone else replace the true down pipe off of the turbo. We played around with a sheet metal fabed up one and didn't see any extra EGT drop or HP gains so we left well enough alone etc.

We have systems in aluminized, T-409 and T-304 stainless in singles and duals as well. Check out the reviews section of this site they did a real nice write up on our T-304 dual system there that pretty much covers everything about the system.

Call us if you need any questions answered.

Mark @ DPPI

I have the catback system with the cat converter left in place and the gains or rather the temp drops were very noticeable even at the engine temp gauge in the dash. Not much for performance just cooler towing thats all.

Mine should be here tomarrow.:D as should be my afe stage 2. I'm excited. Wut kinda tools about i gonna need for the "downpipe" cuz it's look like it's gonna be a driveway job plans for using a lift at work falling through.:mad:

just installed mine LOVE IT! fit and look is awesome. Best sounding exhaust i've heard on a duramax from wut i have heard on them.

How much louder over stock is it? Did it just bolt up as expected? Did you buy the stainless single or if not which one?

i got the turbo back it is stainless it's not as hard as i thought it was. i got the single the magnaflow number is 15976. At an idle is not much louder then stock but it get pretty loud. with the window up there is barely a drone and you can't really hear it with the radio turned up. But wut fun is that. W.o.t it's pretty loud my friend said he heard me coming from a good ways away. i got it at rpmoutlet for 448 shipped. they got a 10% off coupon right now with free shipping.

I just finished putting on straight pipe from turbo down.
When I started up it sounded great. A good rumble.
Then the sound completly changed. It sounded more like a hissing. Sometimes it would go back to the rumble.
This happened every time I started the engine.
What is going on?:confused:

I just finished putting on straight pipe from turbo down.
When I started up it sounded great. A good rumble.
Then the sound completly changed. It sounded more like a hissing. Sometimes it would go back to the rumble.
This happened every time I started the engine.
What is going on?:confused:

That is the blade pitch changing on the VVT turbo. It cycles the vanes at startup.

Magnaflow is all that I run on all of my vehicles. Sounds great outside the vehicle while remaining quiet inside. And quality is second to none IMO. I have the stainless system that comes with the 5" tip factory welded.:ro)

StaticX are you running an LLY? Any codes at all?

i'm lb7 no codes and on the other hand i didn't have a conv. to start with. gotta love havin an 02 and to think i almost bought a 04.5?

And from what I gather the codes aren't that big of a deal anyway, and are easily defeatable with the plates or finger stick. I'm definitely going to by that system. THANKS!!!!!!!

staticx04,

That's a decent price on a Magnaflow, our MBRP systems are less than that and of course we would take care of the shipping or whatever per our price matching policy.

Mark @ DPPI