[Ucffootball87]

Taking price out of the equation, which DP would you go with?

AA 400 cell DP or Fabspeed 200 cell DP. Both are advertised to not throw a CEL. Fabspeed does advertise HP & torque gains.

Current MODs on my 2023 M3 with notes :

- AA single midpipe - Added a deeper tone, pronounced burbles.
- MST intake - fantastic turbo noise , easy install
- Dahler valve controller - Added significant volume all around to cold start and medium rev range. Still tame with stock exhaust
- AA axle back - Smoothed out tone of exhaust and actually created an even deeper, pleasing tone. After cold start, I actually think it's quieter than stock muffler with the above mods.... even with valves wide open.

Would like more sound which is why I'm considering catted downpipes. Any input and experience appreciated.

[mike@x-ph.com]

You cant go wrong with either one, but The active autowerke is the more proven and more popular option. Its also the cheaper option.

[brianray18]

So you think Autowerk is better than Fab Speed downpipes? Do you know how much HP & Torque it adds? The AW?

[TopJimmy]

AA cats are very good quality

[mike@x-ph.com]

Originally Posted by brianray18

So you think Autowerk is better than Fab Speed downpipes? Do you know how much HP & Torque it adds? The AW?

The Active Autowerke (AA) and Fabspeed provide comparable power gains, reliability, and sound, so determining which is "better" might be a bit challenging.
AA cats are EPA-approved, whereas Fabspeed employs European HJS cats, which are not EPA-approved.

The choice between the two comes down to personal preference. The performance you'd achieve from either would be identical.

[brianray18]

Thanks for your input Mike! Do you have the dyno numbers? Ive seen dyno numbers from fab speed but non from Active. Ive seen dyno runs but no numbers, makes me think there are no gains

[IronChad]

You aren’t going to gain much without a tune, if you are doing a downpipe and no tune it’s mainly for sound.

[mike@x-ph.com]

Originally Posted by brianray18

Thanks for your input Mike! Do you have the dyno numbers? Ive seen dyno numbers from fab speed but non from Active. Ive seen dyno runs but no numbers, makes me think there are no gains

The gains are going to be the same with either brand, as they both use high flow cats. I dont think i have a dyno for active on its own but i have seen a few with a tune and i believe it was +15-25 whp

[MrJDS]

Which downpipes did you end up going with? AA or fabspeed. Thinking of doing AA on mine but heard from multiple users that the cold start sound isn't that great but I believe thats with stock exhaust... I have a full valvetronic titanium exhaust so it may not affect the sound that much tho.

[Boogie2121]

Originally Posted by MrJDS

Which downpipes did you end up going with? AA or fabspeed. Thinking of doing AA on mine but heard from multiple users that the cold start sound isn't that great but I believe thats with stock exhaust... I have a full valvetronic titanium exhaust so it may not affect the sound that much tho.

I have full valvetronic + AA, good sound all around. Best sounding setup for this platform imo.

[mike@x-ph.com]

Originally Posted by Boogie2121

I have full valvetronic + AA, good sound all around. Best sounding setup for this platform imo.

[MrJDS]

Originally Posted by Boogie2121

I have full valvetronic + AA, good sound all around. Best sounding setup for this platform imo.

Thanks for the info! Any smell with the AA and have you noticed any power increase?

I know fabspeed advertised a slight increase but AA has not.

[MrJDS]

Originally Posted by mike@x-ph.com

The Active Autowerke (AA) and Fabspeed provide comparable power gains, reliability, and sound, so determining which is "better" might be a bit challenging.
AA cats are EPA-approved, whereas Fabspeed employs European HJS cats, which are not EPA-approved.

The choice between the two comes down to personal preference. The performance you'd achieve from either would be identical.

Does not being EPA approved means it won't pass emissions?

[mike@x-ph.com]

Originally Posted by MrJDS

Does not being EPA approved means it won't pass emissions?

It depends on the state and the emission; in some cases, as long as the downpipe is not triggering the check engine light, you will pass the emissions test.

Whether you are legally passing is a different conversation, which im not an expert on. But the fact that Active Autowerke uses EPA approved cats and is less expensive, makes it the more obvious option.