gtreng1

Has anyone ever considered doing a swap with an OEM exhaust from a 928? They sound pretty sweet, and Im sure would be less than the $2k Miltek wants. Motors are both in the 300-350hp range, both V8's. Anyone here cut out their Cats?

alextimmons

if you were to cut out your cat? I would imagine the O2 sensors would be throwing codes left, right and center. Not to mention the likely flashing CEL.

joneze93tsi

CEL = Always On (after 100 miles)

mAgnum8

I have the X pipe but haven't had a chance to throw it in yet.<ul><li><a href="https://forums.audiworld.com/a8/msgs/169469.phtml">https://forums.audiworld.com/a8/msgs/169469.phtml</a</li></ul>

GSpence

As a long-time 928 fanatic and owner of an S4 and soon a GTS, I gotta tell you that exhaust system won't work or fit. The 928's exhaust system is pulse tuned to the "inth-degree" in stock form specifically for the torque and power delivery characteristics of the various 928 motors. That's why so many guys have so little results with and displeasure with adding headers to the 928 - you really don't need them unless you've radically changed the tuning of the motor. Typically with the 928 if you want real results from an exhaust upgrade, you're gonna spend at minimum $1600.00! For the A8 your best bet is to look for a S8 set-up and have it modified to fit, or lose the rear muffler for a kind of rear muffler bypass thingy. You'll definitely have a louder exhaust, not so sure it'll be sporty though and the torque characteristics of the motor will definitely change - most likely in the midrange.

gtreng1

me think..."will that fit?"

Are there any HP gains from the rear muffler delete and x-pipe addition. Anyone have any Youtube videos?

gondar

OK, you are now OFF Obama's list as head of EPA...

gtreng1

I love my carbon footprint...

gtreng1

Remove middle muffler, throw on xpipe and Supersprint aft muffler.

Keep middle muffler, Remove aft muffler, replace with stright pipes.

Same as abov except with xpipe

The Paul W Supersprint upgrade from his old A8?

You guys might ask, why doesnt he just get an S8?? With my wife wanting a Q7, Ill just hang on to the A8 until it get too unreliable.

jfrahm

They modify the signal from the front O2's the placate the computer. Not sure if you'd get any performance, or if you'd get the sound you want.

The interesting mod to the 928 is the X pipe, without cats though it drones pretty badly. With cats, you have to use small cats amounted farther back as the X is where the 928 cat is located in the stock system. In the 928 I found the drone to be totally unacceptable. A high flow cat or resonator type muffler to catch the backwave might be needed in the A8 to avoid drone.

Me, I like the stock quietness as I can drive briskly without attracting attention. That probably does not impress the high skool kidz but I'm totally OK with that.

-Joel.