[PYCg80]

Berzerker So would it be fair to say if I eventually want to make axleback choices after midpipe & valve controller, the biggest attributes relevant to me are closed valve state sound and open valve drone fighiting, since the mufflers are different in size/composition vs. OEM (or other aftermarket choices)?

Am I wrong/right to focus on these when comparing OEM vs. AM (or AM vs. AM) axlebacks:

1. Closed valve - how well it eliminates drone, sound through muffler, overall sound level, restrictiveness to airflow, integration compatability to OEM valve controller

2. Open valve - drone elimination (or is that more midpipe?), airflow, sound quality (due to piping sizing/configuration/flow vis a vis the muffler), less focus on this vs. closed?

Otherwise for my stated preferences and goals (sound/appearance), does OEM vs. axleback come down to cost/appearance, partially achieveable with AM exhaust tips (plus the diaper effect)...?

[Berzerker]

Originally Posted by PYCg80

Berzerker So would it be fair to say if I eventually want to make axleback choices after midpipe & valve controller, the biggest attributes relevant to me are closed valve state sound and open valve drone fighiting, since the mufflers are different in size/composition vs. OEM (or other aftermarket choices)?

Am I wrong/right to focus on these when comparing OEM vs. AM (or AM vs. AM) axlebacks:

1. Closed valve - how well it eliminates drone, sound through muffler, overall sound level, restrictiveness to airflow, integration compatability to OEM valve controller

2. Open valve - drone elimination (or is that more midpipe?), airflow, sound quality (due to piping sizing/configuration/flow vis a vis the muffler), less focus on this vs. closed?

Otherwise for my stated preferences and goals (sound/appearance), does OEM vs. axleback come down to cost/appearance, partially achieveable with AM exhaust tips (plus the diaper effect)...?

I would say that pretty much any axleback with a closed valve shouldn't drone at all. They're pretty quiet in general.

There isn't much to deciding on an axleback vs OEM. An AM axleback will increase volume a bit but change the sound slightly so it really depends on what you like, which is why I suggested trying to find something to listen to. Most of the big names (active autowerke, valvetronic, dinan, etc.) have figured out how to eliminate drone from their axleback replacements, so you're fairly safe there. There's been one report of the new MAD axleback having a little drone at 2-3k RPM (which is where most drone ends up happening if it exists).

Drone reduction is going to largely come down to muffler quality rather than midpipe.

A large decision factor for an AM axleback does, as you mentioned, come down to wanting to remove the diaper look and improved exhaust tips.

[Info@mad-us.com]

Originally Posted by Berzerker

I would say that pretty much any axleback with a closed valve shouldn't drone at all. They're pretty quiet in general.

There isn't much to deciding on an axleback vs OEM. An AM axleback will increase volume a bit but change the sound slightly so it really depends on what you like, which is why I suggested trying to find something to listen to. Most of the big names (active autowerke, valvetronic, dinan, etc.) have figured out how to eliminate drone from their axleback replacements, so you're fairly safe there. There's been one report of the new MAD axleback having a little drone at 2-3k RPM (which is where most drone ends up happening if it exists).

Drone reduction is going to largely come down to muffler quality rather than midpipe.

A large decision factor for an AM axleback does, as you mentioned, come down to wanting to remove the diaper look and improved exhaust tips.

Highly suggest using the resonated midpipe in this situation.

[NFARVW]

Originally Posted by Berzerker

Either a midpipe-only or axleback-only will require you to cut at the midpipe-axleback joining area. This is normal and is also what BMW does to install the first-party M Performance Exhaust. I would put zero concern in that, specifically.

The recommendation is to start with a midpipe since that gives you the most volume change, as you're removing resonators and secondary cats.

It'd be tough to say one kind or another without having you actually listen to them and see which you prefer. Most people like single midpipes the best as it tends to give a more "deeper throaty" sound compared to equal length or X-Pipe (stock midpipe is an X-pipe config).

If you think you may swap downpipes in the future (this can cause warranty concerns so I'd only recommend if you don't care about that), it's recommended to get a resonated midpipe. If you're not going to swap downpipes, you can get unresonated.

As for axleback, that becomes trivial once you get a midpipe swap as your axleback is already cut from the midpipe, it's just a few screws and some hangers and it's off. Many people actually keep the OEM axleback as it does quite a good job at eliminating drone and is already a straight-piped design with valves open. You'll want to add a valve controller.

TLDR: Midpipe first, then decide axleback.

What plug and play valve controller would you recommend?

[RACE M3]

Originally Posted by tom @ eas

IMHO, the Evolution Racewerks Midpipe + Awron EVC is the perfect combo. Instant attitude at the press of a button while keeping that OEM+ appearance from the outside.

I'm curious how much i can adjust the awron? Ive been debating it for a year and if it can do this i'm 100% sold.

Can i adjust the valve to whatever percent i want based on rpm or throttle percent? Think something similar to boost by gear.

If i could have any setting i'd have it wide open under 2-2.5krpms, close to 20-30% like oem until 2.5-3.5k to avoid drone then open to 50% unless im over 50% throttle.

Then a secondary setting of wide open.


Whats the cost of the Awron shipped?

[FLJayAy]

I was in the same situation as you recently. Decided to go for the full catback from MAD. Honestly I can’t be happier with the sound. Changes the car completely with the deep, aggressive sound and the cleaned up back end. Go for the full system and you won’t be disappointed

[mike@x-ph.com]

Originally Posted by FLJayAy

I was in the same situation as you recently. Decided to go for the full catback from MAD. Honestly I can’t be happier with the sound. Changes the car completely with the deep, aggressive sound and the cleaned up back end. Go for the full system and you won’t be disappointed

+1 to getting a full exhaust for the best sound, but i'd still add the controller for more sound and control

[Berzerker]

Originally Posted by NFARVW

What plug and play valve controller would you recommend?

SST in the other thread.

[tom @ eas]

Originally Posted by RACE M3

I'm curious how much i can adjust the awron? Ive been debating it for a year and if it can do this i'm 100% sold.

Can i adjust the valve to whatever percent i want based on rpm or throttle percent? Think something similar to boost by gear.

If i could have any setting i'd have it wide open under 2-2.5krpms, close to 20-30% like oem until 2.5-3.5k to avoid drone then open to 50% unless im over 50% throttle.

Then a secondary setting of wide open.

Whats the cost of the Awron shipped?

Full details of the Awron CANFlap is in this thread, I'll follow up with a PM shortly:

▀▄ eas | AWRON - Smart CANFlap Exhaust Valve Controller for BMW
https://g80.bimmerpost.com/forums/sh....php?t=1991762

[mike@x-ph.com]

Originally Posted by Berzerker

SST in the other thread.

Cant go wrong with the SST