[NPTM]

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Hey guys - looking to hear from anyone who has installed an AA EL Midpipe on their otherwise stock M2 CS, and has had experience with BOTH the resonated and non-resonated connector pipes. Stock DPs & stock back box...only thing changing here is going from resontated to non-resonated, or vice versa.

I'm plagued with the cold start rasp - not a huge issue for me as I always warm the car up good when it's actually cold, but still less than ideal on an otherwise perfect car because it always happens on start-up, regardless of whether the car is actually cold or not.

I LOVE the sound/volume of my non-resonated setup as-is once warmed up, so I'm torn on whether adding resonators and losing volume is worth fixing the cold start rasp (according to AA, it will). I don't want to lose too much volume / tone...AA says the volume reduction is minimal, but looking to hear from you guys for some real world experience...

What's your best guess on volume reduction if I swap to resonated? Thanks all!

[M3R1]

IMO, the resonated version sounds perfect. I am not a fan of rasp on any exhaust. This is going back to my E46 M3 days. Even back then there were many rasp eliminators available, I of course, had one.

Click the link below and listen to the videos to hear how crisp the exhaust note is with the res version.

https://f87.bimmerpost.com/forums/sh....php?t=1865324

[NPTM]

Originally Posted by M3R1

IMO, the resonated version sounds perfect. I am not a fan of rasp on any exhaust. This is going back to my E46 M3 days. Even back then there were many rasp eliminators available, I of course, had one.

Click the link below and listen to the videos to hear how crisp the exhaust note is with the res version.

https://f87.bimmerpost.com/forums/sh....php?t=1865324

Appreciate it but only videos I see are with aftermarket back box - so not a perfect comparison for me, but point taken on eliminating all rasp, even at expense of volume.

[M3R1]

Originally Posted by NPTM

Appreciate it but only videos I see are with aftermarket back box - so not a perfect comparison for me, but point taken on eliminating all rasp, even at expense of volume.

That is correct, I was just trying to give a little context. I would not consider the Eisenmann Performance Exhaust very aggresssive at all. They even have a race version that is more "aggressive".

My intent for changing the back box was strictly to get rid of the OEM cow udder. My goal was to completely tuck the system and retain an OEM type look to the car. Most of the aftermarket back boxes have tips that are far to large and "tuner" looking.

Im fairly sure that the resonated EL and stock rear section would deliver the clean (no rasp) sound you are after.

Hope this helps a little...

[NPTM]

Originally Posted by M3R1

That is correct, I was just trying to give a little context. I would not consider the Eisenmann Performance Exhaust very aggresssive at all. They even have a race version that is more "aggressive".

My intent for changing the back box was strictly to get rid of the OEM cow udder. My goal was to completely tuck the system and retain an OEM type look to the car. Most of the aftermarket back boxes have tips that are far to large and "tuner" looking.

Im fairly sure that the resonated EL and stock rear section would deliver the clean (no rasp) sound you are after.

Hope this helps a little...

Very helpful, thank you! I hear you on the ugly cow udder...ONLY reason I am keeping the OEM back box is because of the CS tips that I absolutely love...I think they are the perfect look / perfect size and love that they are actual tips and not decorative sleeves like every other OEM exhaust nowadays...I am trying to retain everything about the CS that made it "special" vs other M2s, and the tips are part of that package to me, so I may just end up painting the OEM back box flat black in high temp paint to hide the udder a bit...but completely understand and respect your decision to make the swap, looks like a good setup to me!

[inTgr8r]

Originally Posted by NPTM

Hey guys - ......

I'm plagued with the cold start rasp - not a huge issue for me as I always warm the car up good when it's actually cold, but still less than ideal on an otherwise perfect car because it always happens on start-up, regardless of whether the car is actually cold or not.

I LOVE the sound/volume of my non-resonated setup as-is once warmed up, so I'm torn on whether adding resonators and losing volume is worth fixing the cold start rasp (according to AA, it will). ......

Thanks all!

Sorry to see yet another cold start issue with the AA EL mid pipe!

I'd love to do the EL pipe & keep the OE backbox. (already painted black)
The only thing holding me back is this cold start rasp issue.
This is the first time I've seen word from AA that the resonator fixes the issue.

If you add the resonator, I'd love to hear about the results.

[Golden3ye]

Does anyone have a sound clip of the rasp on cold start?

[NPTM]

Originally Posted by Golden3ye

Does anyone have a sound clip of the rasp on cold start?

Many threads and videos out there, and to be honest I didn’t want this thread to turn into an AA bash because they have been awesome to me, great support, and the product is super high quality…I think at days end, they fixed one of the biggest (and only for me) issues with this car, and in the process, you have to accept some slight side effects (cold start). I’ll make that trade 100x over, this thing sounds nuts now, exactly how I wanted it aside from the start. I get why some guys got upset a few years back when this info wasn’t out there…but now we know what the trade offs are, and it’s still worth it for me without question.

Gonna likely slap the resonators on when slow around holidays so I have time to swap back if the results aren’t as desired - if I’m gonna lose some volume, it better fix the cold start…if not, I’ll take my volume back haha.

Stay tuned!

[MSH_]

I hope to be able to speak to the differences soon as I have both the non-res and resonated pipes. I actually wanted to install the resonated pipes first but they wouldn’t fit so I installed the non res pipes. Fit was very tight on the drivers side pipe (even after checking my AA suggested cut marks 10x before cutting). I still ended up having the melted diffuser issue many have had here on the forums. Fortunately i was watching it closely so i only had very minor melting in one small spot. I ended up getting back under the car yesterday and cutting an additional 1/2” off the drivers side pipe which I think will resolve the issue.
While I had the non res pipes out I measured them to compare to the resonated ones AA sent. What I found is that the longer drivers side non-res pipe is a full 1/2” shorter vs the drivers side resonated pipe. It’s no wonder the resonated pipe didn’t fit. The shorter passenger side non res pipe is 1/4” shorter vs the passenger resonated one AA sent. Also the drivers side resonated pipe has a noticeably larger OD. AA sent me two different size torca clamps (63.5 and 63) The larger 63.5 couldn’t even fit over the larger OD resonated pipe.
I mention all of this so those of you that decide they want to swap to resonated pipes from non res pipes to take measurements or you risk getting under the car and have issues once you have everything apart. At this point I just think AA’s QC is just not great. The setup sounds great on my car but these guys need to tighten up their s**t. It’s really annoying and a waste of cycles for everyone.

[NPTM]

Interesting on the different clamps…I assumed mine were identical, good to know.

I got my non res pipes fitting perfectly so if there’s a clearance issue on my res pipe, I think I’m cutting the res pipe and not my back box again. Will be easier to do off car, and if ever decide to go back to non res, it will still fit as well. But I hear you that shouldn’t even be a concern / consideration.

Either way, your comments above make me want to do this swap when I can leave the car jacked up for a week if needed…

[MSH_]

Originally Posted by NPTM

Interesting on the different clamps…I assumed mine were identical, good to know.
I got my non res pipes fitting perfectly so if there’s a clearance issue on my res pipe, I think I’m cutting the res pipe and not my back box again. Will be easier to do off car, and if ever decide to go back to non res, it will still fit as well. But I hear you that shouldn’t even be a concern / consideration.

Hopefully you received the correct Torca clamp size. According to the instructions, and if you just order them ala carte off their website for any F8x midpipe, they are supposed to be 65mm clamps. I received a 63mm and 63.5mm...again just sloppy work on their part.

Agreed on the cutting the resonated pipe. I already had to cut that additional 1/2" off muffler/back box drivers side pipe, so I'm not cutting any more off that side.

Anyway, best of luck!

[NPTM]

Great call on the clamps - would have been really frustrated if I couldn’t complete the job in one push. Reached out to AA for them, thanks! Will be back with thoughts after I make the swap.

[Apexeater]

I might be of some help. I have your exact scenario minus being a M2CS. I have a 21 M2C. I started with the non res version (AA EF mid pipe) and factory back box and DP. Mine had the starting rasp you talk about and the resonators eliminated it for me. The volume reduction was minimal and it made the exhaust note more mature sounding to me. I am very happy with the sound now.

[NPTM]

Originally Posted by Apexeater

I might be of some help. I have your exact scenario minus being a M2CS. I have a 21 M2C. I started with the non res version (AA EF mid pipe) and factory back box and DP. Mine had the starting rasp you talk about and the resonators eliminated it for me. The volume reduction was minimal and it made the exhaust note more mature sounding to me. I am very happy with the sound now.

Awesome to hear, that's exactly what I was hoping for. Definitely going to do the swap, now I just need AA to answer me about the clamp difference mentioned above...don't want her sitting on jack stands for too long. Appreciate the input!

[NPTM]

Update - put the resonators on yesterday. Startup rasp gone…so that’s a huge positive. I haven’t had her out on the streets yet given a recent snow in NY, but only negative I can hear from revving in my garage is a bit more volume reduction than I hoped for, BUT I need to get street time on her to make that call.

Either way, volume aside, that brutal cold start rasp is gone and that was my main goal…so mission accomplished and thanks to AA for working with me along the way!

[Syed///M]

Glad to hear it worked out!

While we're on this topic. anyone here tried the EL Res midpipe with an Eisenmann RACE exhaust? seems like a rare combination, was not able to find any posts with this setup.

[NPTM]

OK guys, finally got out for a proper drive with the CS post AA EL resonator install. My impressions…

1. The car is significantly quieter than expected, much more so than the slight reduction AA implied. I’d say more like 25-30% quieter vs non-res. Not sure if that will change as the resonators break in, but initial volume reduction is material. Still louder than stock of course!

2. Cold start rasp solved, and that was my main goal. 3 more starts since install, and that cringe worthy sound is gone.

3. While quieter, the sound is seemingly much more “mature” - not sure how else to describe this. The sound is more uniform, more collected, more smooth/ even vs the un-res which at times felt unpredictable and occasionally obnoxious (high rev gear shift). So I think despite being less exciting, it’s a higher quality sound.

4. The moderate drone I had is gone, and that has returned a sense of quality to the cabin that I didn’t realize I was missing.

**Install note! The driver side resonated pipe was a good .5” longer than my un-res pipe. Since I had the fitment perfect on the res pipe, I didn’t want to cut the muffler more on the chance I ever swapped back, so I decided to cut the resonated pipe before puttting it up. Also, same clamps worked so no issue with diameter like mentioned above.**

[DadVibes]

Great to hear the resonated connecting pipes solved your issue. I have non-resonated connecting pipes for the stock muffler + resonated connecting pipes for the AA muffler.

Due to AA's horrible QC and poor fitment of their muffler, I've found myself going back to the stock muffler a couple of times. As that resolves the clearance issues with the AA muffler piping rubbing against the subframe.

However, what's kept pushing me back to the AA muffler (and consequently endless fitment troubleshooting), is the obnoxious rasp of the stock back box with non-resonated connecting pipes. Both cold start and while driving. I've thought about ordering a set of the resonated pipes for the stock muffler. But given how much I've already spent on AA parts, the thought of throwing another $500+ at them just doesn't sit well with me.

[MSH_]

Originally Posted by DadVibes

...However, what's kept pushing me back to the AA muffler (and consequently endless fitment troubleshooting), is the obnoxious rasp of the stock back box with non-resonated connecting pipes. Both cold start and while driving. I've thought about ordering a set of the resonated pipes for the stock muffler....

Enabled can help you with that! I had it as well (like most everyone) with stock exhaust+AA EL MP+Non-res connecting pipes. He made some tweaks to the tune to shorten cold start and I guess some other magic to make the rasp nearly non existent. The only time its an issue is on cold start and I immeditely throw in reverse to back out of garage, which I never really do. I always let it warm up for 30 secs at least before backing out. I still wanted the loud cold start when I wanted it so Enabled reduced cold start routine to about 30 secs from stock which is like 1.5-1.75 mins. He can reduce cold start routine to zero if you want it that way. I just like having the option of louder cold start in Sport or Sport plus and when I want it quiet go to Efficient.

[DadVibes]

Originally Posted by MSH_

Enabled can help you with that! I had it as well (like most everyone) with stock exhaust+AA EL MP+Non-res connecting pipes. He made some tweaks to the tune to shorten cold start and I guess some other magic to make the rasp nearly non existent. ...

Enabled tuned my Comp and the difference in sound/power/drivability was extremely impressive.

If my CS didn't require physically removing and shipping the DME out, I'd have him tune it in a heartbeat. I just don't have the energy for that type of project.

[cwunch]

Can someone post the rasp sound clip?

I am also planing to remove the opf’s and mid silencer, keeping the original back box (I also like the tips a lot) and stock dp.

[NPTM]

Originally Posted by cwunch

Can someone post the rasp sound clip?

I am also planing to remove the opf’s and mid silencer, keeping the original back box (I also like the tips a lot) and stock dp.

Several videos out there on this forum and YouTube...I didn't find them until AFTER I installed it, which was unfortunate as the rasp definitely frustrated me more and more over time. I will say, the car sounded EPIC once warm...but before warm it was just brutal, even with the flaps closed it sounded bad to me. That's all subjective, but it was enough for me to throw in the towel...and a big part of that was it happened on EVERY start, not just when cold, and the rasp would stick around for several minutes, sometimes 5ish...so I found myself never wanting to shut the car off while out for a drive.

Resonators = fixed...but it lost some of it's visceral sound, and that sucks...BUT the induction noise is much more aggressive to me now, as I put my Eventuri intakes on AFTER I did the exhaust...so now I am enjoying a nicer induction/exhaust balance.