How loud will this be?

[dougsic]

Loudness is a subjective thing, but this will be F&^%$'in loud! And the worst thing, it will drone like a broken truck at around 2-3krpm, i've been there.

Static is the winner! You are absolutely right!

Loudness is subjective - when driving this car, it is the subject of everyone around me.

Before doing the exhaust this way, I had the ebay headers connected to the stock e36 M3 midsection and rigged onto the stock e30 325i muffler. The exhaust was silent until WOT when it hissed a bit. I felt the muffler was strangling the exhaust and I still feel that way.

Now, the car is so freaking loud I hardly drive it as I'm embarassed. And worse, exactly as Static stated above, the drone in the car is overwhelming. With a passenger, we are nearly shouting at each other to be heard. No, we ARE shouting at each other to be heard. My wife actually said that the car is louder INSIDE than it is outside and she refuses to ride again until it's quieter.

Even when I barely tip into the throttle, the volume increases unbearably.

I would love to brag to you guys that I welded the exhaust up in my garage but the truth is I didn't. I paid dearly for it. Sorry Ed. The tubing is SS 409, mandrel bent. I had the converter installed with v-bands and a track pipe made for it - well, that will never get used!

The resonator was installed after I took the car back to the shop complaining that it was too loud. Because the exhaust is so tight to the underbody, there was no room for a chambered resonator so this one is straight through. It made only a barely noticable difference.

Enough whining.

The flex pipe is installed so that there isn't any binding going on between the headers and the rest of the system since the exhaust is welded directly to the headers (no flanges).

I didn't know the shop was going to weld the exhaust to the headers or I would have protested. Look closely at the first picture in this topic - how in the world can I ever remove the headers? They are effectively welded together now! Looks to me like I would have to cut them apart or pull the engine to get them out?

Here is a picture of the rear valance and the tips. Sadly, they look really nice - they don't stick out too far and are well centered.

The car goes back to the exhaust shop on Wednesday morning for a different muffler. If that doesn't help enough, I may ask for a chambered resonator in place of the catalytic converter. I hate to be a polluter but I hate more to have this fun car that I can't stand to drive.

[static]

^^ my condolences and i hear you on the frustration.
It really sounds like you should change your exhaust/welding shop. Thankfully, cutting and welding up couple of flanges on headers won't cost you a fortune.
As i mentioned in my PM, stock e36m3 muffler fits (with just a bit of underbody massaging and good angle) but it will probably defeat the purpose of having headers as it's baffled=restrictive, plus it's very heavy. But i do agree that peace of mind is more important than a few horses/pounds .
Another option is as i mentioned 5x11x22 magnaflow, which fits again at a proper angle (i have single in single out)
I was inspired by this dude:

http://e30m3performance.com/installs/installs-2/exhaust/exh1.htm

but as i mentioned, i'd like it even quieter, so another muffler instead of my 4x22 res is in order.

Alex

[SchnellerVert]

The resonator is to close to the muffler. It needed to be back towards the engine and needed to be bigger.

Very sorry you are having this issue. The exhaust shop did the mention this?

How about doing reverse DTM tips toward the ground. This will absorb some sound and be viable cheaper alternative to tearing it apart.

By not exiting the body it's reverbing under the car. Arg no the drone feeling, used to have a TechTonics Tuning on my VW, while it made great power thru out the entire band it was obnoxious at the standard 16V cruise range on the highway at 3300 to 3700rpm. Gutted Scirocco's are known to do that thou.

[matt]

The resonator is to close to the muffler. It needed to be back towards the engine and needed to be bigger.

Very sorry you are having this issue. The exhaust shop did the mention this?

Come to think of it... those are the two differences between this setup and mine. I have a 24" cherry bomb where he has his cat. Smilar magnaflow though.

[static]

The resonator is to close to the muffler. It needed to be back towards the engine and needed to be bigger.

This is true at least theoretically. From what i read, the nasty resonance/drone is born not in muffler but rather in the pipe. Like in organ, it depends on lenght/diameter of the piping. Resonator is meant to break the resonance by "splitting" up the pipe into two shorter ones, which should help with breaking up the resonance frequency.
When i installed my 22" magnaflow res. instead of hiflow cat, it made sound smoother (got rid of rasp) and helped a tiny bit with resonance/drone but definitely have not eliminated it.

my conclusion was that if you want quiet but still free flow, you have to go big and multiple (as in big and multiple mufflers)

[SchnellerVert]

Big is not always good you will loose velocity and this does not help.

Your right, it's not the mufflers it's the pipe harmonics and the resonance from the engine, Straight sixes make a distinct sound. All very similar.

The down turned pipes will help to a degree this is why all the major manufacters are doing this, it cuts the sound down while allowing them use of larger tubing. Reverse of DTM.

Also, thinking the straight pipes don't help in the least bit. The get to shaking in a rythmic fashion.

How loud is it truely?

[Aerton]

small straight through resonator into Magnaflow single in, dual out exhaust?

Hey can we get a sound clip of that setup?
Thanks

[matt]

Big is not always good you will loose velocity and this does not help.

Bigger is better with mufflers. Bigger muffler = better sound control. Bigger pipe is not always better though.

Turndowns do help.

[SchnellerVert]

Bigger is better with mufflers. Bigger muffler = better sound control. Bigger pipe is not always better though.

Turndowns do help.

yup thought he meant pipes. Fine detail missed it.

[FredK]

I bet it'll set off car alarms. Is that Magnaflow 3.5x7x14"? It looks very small. I can't really imagine that the resonator does too much to alter the sound.

[static]

i was toying with idea of adding some sort of valved exhaust setup: direct the flow through a restrictive muffler before say 3.5krpm and redirect flow through something free-flowing past 3.5krpm. The valve can be controlled with some sort of logic based on rpm and tps signals.

maybe one day..

[Aerton]

I don't want to sound too old but, when I was into VW Jetta's there was more knowledge of what was too big a system. If you do not have the right system you are not pulling the exhaust out of the car fast enough. And that gents is what the whole story is about, how fast you can process air through your whole car, air intake, plenum, combustion chamber, exhaust.

That is why Honda's are made and tuned with broom stick exhaust pipes (at the Factory) and 4" muffler and pipes take their place, then they sound like a Mustang with straight pipes and perform like Honda's without an exhaust system.

There is a science to exhaust systems, and I'm sure some of the racers in this site can tell you what works not what sounds good. Right now I have a problem with my new ANSA, it sounds like stock system and I hate it but I'm sure it is tuned to the car or hope it is.

[dougsic]

Lots of good feedback here. Thanks to everyone for your thoughtful contributions!

As I mentioned in my follow-up post:

"The resonator was installed after I took the car back to the shop complaining that it was too loud. Because the exhaust is so tight to the underbody, there was no room for a chambered resonator so this one is straight through. It made only a barely noticable difference."

Yes, it's too far back but it was the only one on hand at the time that would fit anywhere in the system.

As loud as the exhaust is, and it's loud, it's the resonance that is deafening. Eeven when I gently tip into the throttle, immediately the volume rises. So much that if you were driving near me, you would know exactly when I added throttle and exactly when I eased off.

I'm scheduled for a new muffler tomorrow morning. I'm hoping it's chambered. At this point, I'll give up any reasonable amount of power to be quiet again.

If the new muffler isn't enough, I may replace the cat with a second muffler.

I've been putting money aside for a twin screw SC next year. Maybe I should think turbo instead? ;)

[static]

^^ i vote turbo, thats what i would do. I hear us s50 easily widthstands aroudn 14psi with just a proper gasket and studs. GEtting this power to wheels in e30 is another question.
After you put turbo on, perhaps you won't need chambered anymore as the turbine will muffle the exhaust, and you will need this flow.

[e30polak]

even though i've been criticized for my header choice, the exhaust system itself is a work of art...i'm running 3" all the way back from my turbo manifold, with a high flow cat, a borla 3" race muffler as my resonator and a vibrant street power 3" turbo muffler...it is much more bearable with the 3.25 lsd then when i had the stock 3.73...however, past 4 1/2 grand u don't want to be next to my car