That's right, I'm going catless. Will be taking off my Cobb DP and replacing it with a Stromung divorced wastegate (image link) and the "race pipe" (3rd cat eliminator) I had on there before I got the long DP. Keeping the rest of the exhaust the same. Swap will happen sometime on the weekend of Dec 9-10.

Just thought you all might care a little bit. I'll be taking before/after sound clips and video for comparison.

 

fumes FTW!

 

One ? Why devoiced? what are the advantages?

it looks like a nice piece though

 

Not entirely sure if there's dyno plots that show that divorced is better than bellmouth or vice-versa, but the Stromung DP is cheap ($195), I have the race pipe that mates to it already, and I can sell my Cobb.

Some say that having the wastegate gas stream merge in further down the DP helps with spool by having less turbulence right outside the turbine exit. This sorta makes sense, since the turbo spins due to the pressure differential across the turbine. I guess I'll find out what the butt dyno reads.

Either type is better than the "flat plate" style that the stock DPs use. (see also: Downpipe FAQ on NASIOC)

 

Since your old Cobb DP has the one cat in it I'd probably be interested in buying it off of you. I'll e-mail cobb to confirm 06' fitment. I'm pretty sure it'll fit since it replaces that entire section.

Oh a sidenote, ever isolate our "whistle" noise? I just got finished being sick and haven't had time to even mess with mine.

I've subscribed to this thread about it........ check that guy's video... same problem... Strange Whistle Sound ? - Page 3 - NASIOC

 

Nate over in Orlando has first dibbs on the DP, but you've got second.

As for the shreak, its exhaust. It comes and goes now and an intake leak wouldn't. I'm just going to ride it out until I replace the DP so I can get to the UP->turbo studs easier, then retorque everything.

 

Well, I don't think it'll be on next weekend. Vendor is getting a new shipment next week, and I'll likely be having it ceramic coated, which will be some extra time. Oh well, I'm probably going to be traveling a bunch for work this month (I've been in Minneapolis all week) and my monthly auto-x is tomorrow, so I'm not in a big hurry at this point.



Post #800!

 

OK, installed it today annnnnnd... it leaks. Well, the 3rd cat replacement pipe leaks. The flange is warped, so I gotta figure out wtf I'm gonna do for that.

Sounds nicer though, same tone but louder, which is what I was hoping for. Reset the ECU so it'll learn around it. Under-hood heat is definately decreased now that all the exhaust that can dump heat in there has been coated.