Amg63-

why are turbo back down pipes not good for the AWD E?

Amg63-

if the stock resonators are not a straight pipe design your probably right, but if they are I doubt they would add any more power with catless DPs. Correct me if I'm wrong.

shardul

iTrader: (1)

Engine has to come out for install

godrealm06

I have the Speedriven catless downpipes and tune. Running two months. No problems. Have an appointment to get my car dyno'd on march 3rd to see how much I'm putting down. You don't need to remove the motor or anything to install them. It's straight bolt on. If you park in garage you will smell gas but honestly it's not that bad. The car is definitely louder when you hit the throttle and when starts cold. During cruise it's almost like stock. I'm thinking of doing a muffler delete too. I feel it needs to be a bit more louder.

shardul

iTrader: (1)

These are turbo back down pipes that we offer.
Godrealm06 you have the down pipe section which does not require engine removal on a AWD car. If you had the portion that replaces the OEM turbo out then the engine would need to come off for install

AG6

From what I am gathering these are options for gains and sound:

Cat back exhaust: Minimal gains, louder sound, high cost
Resonators removed: No gains, louder sound, low cost
Down pipes: Maximum gains, louder sound, medium cost

If that is correct then DPs are the way to go

Amg63-

^ I would just add to that to make sure the downpipes are a catless downpipe setup at the minimum.

KLR CLS

These are the best DPs for the price. I am running same ones and they made huge difference in torque. Sound is great, and I paired with 3" full custom turbo back and sounds amazing!

TMC M5

I have a set of Speedriven downpipes with high flow cats (HFC). I have put over 1K miles on them with no CEL (I have had HFCs on other cars and still got the dreaded CEL, so that isn't a given). For me, this is an ideal solution for my needs: louder/better sound without being obnoxiously loud (check), no CEL since I don't have an ECU tune (check), a little bit quicker spool in the mid-rev range (check), no obnoxious smells when car is idling (check).

But if you are looking for really loud and maximum power you should go catless.

jrosa

Does someone have the Alpha downpipes installed and could post a video so I could check how much louder the car gets running with it?

Chappy

What about doing electronic exhaust cutouts? Maximum sound - can this be done post-cats?

AG6

Are you talking about a cat back exhaust? From what Im reading the AMG exhaust is quite efficient as it is.

gaspam

no he's talking about electric cutouts where a value opens via push of a button to open value and vents exhaust gases and sound as opposed to traveling through rest of exhaust

and yes, this would make a lot more noise

Amg63-

Would doing this be similar to the stock RS7 exhaust where pushing a button makes it louder/quieter?

chiromikey

Not really. Doing this type of valve opens the exhaust before the mufflers so that there is zero noise reduction. The Audi's valves are in the muffler and just open up a second chamber so it gets louder but the noise is still reduced. Most cars sound like crap with no noise reduction...but I'd still love to hear the M157 unrestricted at least once.

TMC M5

+1

I would love to hear it....not sure I would like to live with it.

shardul

iTrader: (1)

They have one in Houston with straight pipes. Sounds too choppy / pops / bangs etc

Chappy

In theory, when the valves are closed, it sounds stock. Hit the button and the exhaust valves open on demand for straight through sound.

Questions in my mind are:

Can these be installed post cats, but pre resonator?
Would this throw a code?
Is there enough room underneath for a clean install?

gaspam

turbo's to an extent muffle and prevent us from having that nascar V8 insanely loud sound like you can get out of C63 M156 or any other n/a v8.

and cutouts shouldnt throw codes since they are post o2 sensors

Airbrush1

Oooh I had contemplated cutouts as well

CarHopper

I strongly recommend against cutouts. For some cars they are great, but in ours our sound is so refined that when you put in cutouts it's just a 5.5 v8 dumping sound. Might as well just have an open dump tractor or something.

Just my opinion.

On the other hand -- You can close them so just open it for very rare occasions.

Admittedly, I had one on my big turbo STi and yeah, it sounded cool. But it broken open once and this was back when I was scraping for change so I dealt with it but it was embarrassing.

Amg63-

Would you say sound is better with a full exhaust system vs catless downpipes with stock mufflers?