Performance exhaust vs OEM Mod

[nchan50]

Originally Posted by kmarei

yes i have
i heard both the original mod and the acm mod
2 cars, right next to each other
one had a very noticable drone (ACM)
one didn't(original mod)
and the owner of the ACM mod car said the same thing
on the highway the drone is very obvious, past 3000rpm

how can you not have drone on what is essentially straight pipe?
the acm style doesn't pass through the muffler box at all

I've had the ACM mod for months and there is some slight drone at around 3000-3200 RPM's which is only noticeable in 5th - 7th gears. It really isn't that bad and some people might be more sensitive to it than others. It doesn't bother me (or my fiancee who is hyper sensitive) and the easy solution is to hold a lower gear for a little longer. If you're cruising in 7th gear, there will be some minor drone at 77-80 mph. You could keep it in 6th gear and it will disappear but again it really doesn't bother me. I love the sound of it and don't think it's obnoxious if that's what you're worried about. Just have to hear it in person.

[kthxbye]

Originally Posted by Prince_of_Persia

I did it this way too, around 50% louder than stock.

Louder, but not loud to where it takes away from the driving experience. Even with the windows down it is just the right amount of sound - this is what I'd expect the M3 to come from the factory with. I've already put 200 miles on it since Friday and it is the best bang for the buck you will find.

[studntloan]

Originally Posted by dagolfpro

I think each individual's own definition of "drones" is different. I did the ACM method and have had various friends in my car and everyone one of them says it's much louder and can hear the exhaust but none have said it "drones".

I was told and from what I've read online, that "drone" means vibrations. Can anyone elaborate on this?

true, people have different meaning to it and different views, especially on loud. etc..

My gintani race muffler was LOUD, my full hjs gfc ae mid pipe and akra slip on is quiet, so it depends on the person

[kthxbye]

Originally Posted by Alex@AUTOcouture

true, people have different meaning to it and different views, especially on loud. etc..

My gintani race muffler was LOUD, my full hjs gfc ae mid pipe and akra slip on is quiet, so it depends on the person

I wouldn't say it adds any drone, but it does very slightly amplify some resonance that is already there on the stock exhaust. Not anything that any passengers have even mentioned or anything that takes away from the driving experience.

I drove an E92 with a Meisterchaft GT2, and although it sounded amazing it definitely added some drone that could get old if you DD. The Z06 I sold in order to get the M3 was the definition of drone, not only could you hear it - but you could feel it.

Engine swap, cammed, full headers, cat-less x-pipe, aftermarket exhaust - the drone would literally make my fillings hurt after about an hour cruising at 70MPH. My solution, drive faster

[tibra1]

Originally Posted by dagolfpro

I think each individual's own definition of "drones" is different. I did the ACM method and have had various friends in my car and everyone one of them says it's much louder and can hear the exhaust but none have said it "drones".

I was told and from what I've read online, that "drone" means vibrations. Can anyone elaborate on this?

Drone is charcterized by a low frequency "hum" in a certain RPM range since its low frequency it does often feel like vibration.. as a result of resonance..its the kind of sound that causes pain in the ears after prolonged exposure

[alpina527]

Can someone throw a link to the finalised version of the top entry diy method please. I've read various posts on different methods and would like to find a method that gives me as close to the M performance muffler as possible

[studntloan]

Originally Posted by alpina527

Can someone throw a link to the finalised version of the top entry diy method please. I've read various posts on different methods and would like to find a method that gives me as close to the M performance muffler as possible

the one we have is as closest as it gets to oem performance one

[serranot]

Originally Posted by Alex@AUTOcouture

true, people have different meaning to it and different views, especially on loud. etc..

My gintani race muffler was LOUD, my full hjs gfc ae mid pipe and akra slip on is quiet, so it depends on the person

True.

There's a j*ck*ss with a Saleen Mustang that trolls through my neighborhood at 30 mph and I can hear it coming for 1/4 mile; that's too loud for the street.

[dagolfpro]

Originally Posted by tibra1

Drone is charcterized by a low frequency "hum" in a certain RPM range since its low frequency it does often feel like vibration.. as a result of resonance..its the kind of sound that causes pain in the ears after prolonged exposure

Thank you for the explanation. By this definition, my car does not drone at all. Since the mod, I've gone over 70 mph and haven't heard/felt any vibrations at all in my car.

[kmarei]

I guess it depends on what you're after
I wanted something that was similar to stock, but a little louder
Original mod is just that
If you are considering some of the aftermarket options
Then probably you are in, what I at least, consider the loud group
Nothing wrong with that
But I don't want an exhaust that I worry about every time I pass a cop etc
I'd say my mod is stock + 20% more volume
ACM was at least 50% louder

[kthxbye]

I put up an in car video at the end of this thread, check it out - http://www.m3post.com/forums/showthr...5#post11523435

[thorny]

Originally Posted by kmarei

I guess it depends on what you're after
I wanted something that was similar to stock, but a little louder
Original mod is just that
If you are considering some of the aftermarket options
Then probably you are in, what I at least, consider the loud group
Nothing wrong with that
But I don't want an exhaust that I worry about every time I pass a cop etc
I'd say my mod is stock + 20% more volume
ACM was at least 50% louder

I have to agree with everything this forum member says in this thread. I had ACM method done, it is indeed loud, but lots of people like it loud. What I did not like was the fact that I had to pick right gears to keep the drone under control. I am not an expert on dronning issue, but what I am referring to is the extra tone you get from your exhaust and you wish it wasn't there when just crusing around town or on freeway. I ended up selling it, if I were to do everything over again, i'd go with the Old Style mod.

[alpina527]

Originally Posted by Alex@AUTOcouture

the one we have is as closest as it gets to oem performance one

That's not the message I'm getting from other users in this thread.

I don't want it to be 50% louder. I wan't it to be about 10-20% louder at WOT and pretty much stock at cruising. Drone is an absolute no no.

Everyone has different requirements from an exhaust and I'm definitely on the conservative side

[kthxbye]

In response to pure volume I still would not say the ACM is 50% louder just moving around town, but yes it is louder than stock - but from what I've heard in person still a quite option in comparison to other exhaust.

In regards to drone/resonance, the ACM drones exactly the same as the stock exhaust, it is just at a slightly higher volume.

With both those points made, the M-Performance Exhaust will do exactly the same thing. From my experience riding in a car with one the drone is just slightly more noticeable due to the different pitch caused by the different type of metal.

When I first read this exhaust drones I thought I had decided right there that I do not want this. I came from a car that droned horribly and wanted to avoid that at all cost. What did me in was when a customer at ACM allowed me to go for a ride in his car while I was getting some other work done. I'm glad he did, because it saved me $3-4,000 on a different exhaust system. Not to say I won't still go the route down the road, but for now I saved a ton and got the incremental increase I needed to enjoy the car a bit more.

This exhaust, like all options, is not for everyone. If you are considering an exhaust, I do urge you to try and get some seat time in a car with the mod before drawing a conclusion, even more so if the alternative is the M-Performance. It may be just what your looking for at a fraction of the cost.

[serranot]

Originally Posted by alpina527

That's not the message I'm getting from other users in this thread.

I don't want it to be 50% louder. I wan't it to be about 10-20% louder at WOT and pretty much stock at cruising. Drone is an absolute no no.

Everyone has different requirements from an exhaust and I'm definitely on the conservative side

Old style mod is perfect for you.

When I bolted mine up and drove it the first time, it exceeded my expectations. It was *exactly* what I wanted.

It sounds like you are looking for a similar sound.

[kmarei]

Originally Posted by thorny

I have to agree with everything this forum says in this thread. I had ACM method done, it is indeed loud, but lots of people like it loud. What I did not like was the fact that I had to pick right gears to keep the drone under control. I am not an expert on dronning issue, but what I am referring to is the extra tone you get from your exhaust and you wish it wasn't there when just crusing around town or on freeway. I ended up selling it, if I were to do everything over again, i'd go with the Old Style mod.

that's exactly my issue
i would want to change my driving to suit the exhaust
avoiding certain gears or keeping below a certain speed
with the original mod, i drive the same as i did before the mod
except i get a little bit more sound
what would rock is a switch on the inside that would switch from ACM mod to original mod
i'm sure it can be done
and would probably still be cheaper than the M performance exhaust

[kthxbye]

So back to the OP question, I think we all agree that the M-Performance Exhaust is way overpriced when you get not only a near identical auditory experience from a modded OEM exhaust for a fraction of the price.

[W///]

I think if you are unsure of which way to go with the OEM mods, this will probably be the way to go

1) Start off with the old sytem OEM mod. Replace all perforated holes with solid ones

2) If the car is still not loud enough, then do ACM method. Yes, you'll have to cut open the exhaust twice, but you can't reverse the ACM method (cheaply) once it's done.

Even if you did both, you'll still would have spent less money than buying those expensive exhausts IMO. I'm going to go with that route.

[cntgetm3]

Now it seems I gotta take a trip to Jersey...

[serranot]

Originally Posted by cntgetm3

Now it seems I gotta take a trip to Jersey...

Stop here in Northern Virginia. Be happy to show you my version . . .

[cntgetm3]

Which mod do you have the ACM?

[LarThaL]

Originally Posted by dagolfpro

I think each individual's own definition of "drones" is different. I did the ACM method and have had various friends in my car and everyone one of them says it's much louder and can hear the exhaust but none have said it "drones".

I was told and from what I've read online, that "drone" means vibrations. Can anyone elaborate on this?

"Drone" to me is an unpleasantly loud bass hum. You can even tell that it is there with the bone stock exhaust, but the volume level has been muted down. You get it right around 2000 rpm while under load with the stock exhaust.

Depending on the system, the loudness of this bass hum and the frequency range that it is present at will vary. You really don't want it between 2-4k rpm, becasue this is where we do most of our cruising around. Honestly....can give you a real headache.