How loud will this be?

[1990m3]

bumping an old thread as I'm working on my exhaust redux project right now...

How much ground clearance does a system like that have where it passes under the subframe and half shaft?

I'm thinking mine might sit a little low there but it's hard to say with the car up in the air.

Pics of anyones setup would be helpful

[static]

do tell

[dougsic]

you know what's loud?

straight pipes from the cat to the tip.

no muffler or resonator.

yeah, I daily drive it.

WOW! Do you have neighbors? Do they hate you?

BTW - That's a nice looking car you have there.

Well, I got the exhaust fixed today and it is quiet. Ahhhh. But it wasn't without surprises.

Maybe I'll start another thread about it next week when I get back home.

Again, thanks to everyone that replied to this thread. Your input was thoughtful and intelligent and I appreciate that.

Doug

[92 mtechnic cabrio]

you know what's loud?

straight pipes from the cat to the tip.

no muffler or resonator.

yeah, I daily drive it.

[matt]

I don't think I saw this mentioned yet, but having a complete dual pipe exhaust should help with the noise and probably drone.

True, but its much heavier. I would go with a larger muffler, and another resonator (different length, same diameter) closer to the motor.

[mazur]

I don't think I saw this mentioned yet, but having a complete dual pipe exhaust should help with the noise and probably drone.

[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

[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.

[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? ;)

[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.

[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..

[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.

[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.

[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.

[Aerton]

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

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