Exhaust Volume and Tail Pipe Question
 

Yesterday the muffler on my 98 E300 fell off. So I went to the exhaust shop I've used for years and, not really having the time to source an OEM muffler and wait for it to come in, opted for a Magnaflow....$200 out the door.

Now driving the car I notice an odd sound, kind of a "whooshing," at around 2300 rpm as I accelerate. At first I thought that this might be some sort metallic resonance or the sound of the turbo. But with my son riding in the car he seemed to think it was coming from the rear...which has led to a new theory.

The original muffler had two pipes; the new one has only one, and it curves down. Is it possible that the sound I'm hearing is due to air constriction or the flow of the air out of the pipe? that, as higher exhaust volume is being forced out the one pipe, it's making the whooshing sound that I'm hearing?

If it's simply a matter of a new occasional sound, it's not a big deal. It's my son' DD and he doesn't care about such things. I'm more curious than anything else.

In retrospect, I wish I had just driven a muffler-less car for a while and ordered the Mercedes part....only $300 or so.

Thanks.

Magnaflow makes VERY good stuff and will likely last a lifetime. Their mufflers are designed to have very low restriction and if anything have LESS restriction than did the OEM part. It will, however, probably have some difference in sound from the factory unit.

Bear in mind that it's unlikely that Mercedes makes their own mufflers and their source may change from time to time depending on who got the current contract. Therefore, any individual muffler may have a somewhat different sound signature depending on the maker so even a Mercedes-sourced muffler may not sound like the older one.

My advice - don' worry, be happy!

Dan

Thanks, Dan. So I gather the one pipe vs. two pipes matter is a non-issue?

The two pipes coming out with one input pipe.I always considered it just an attempt at style. By the cars designers. As for the whoosh noise I have no opinion.

The dual pipes do have a purpose. No it isn't to provide greater exhaust volume, it's to attenuate noise. Two smaller pipes will have less "drone" than one larger pipe will and they're slightly more restrictive. All things being equal, 2 small pipes with the same cumulative cross section as a single pipe will flow less gas with slightly more restriction.

I'd imagine what you're hearing is just the engine breathing a bit easier. With less attenuation, you probably also hear the turbo more.

Thats normal on an aftermarket muffler specially on a turbo car, you are hearing free flowing air.

on my W210 the original muffler rusted at the weld, I got a bosal one out of a car from the u pull it junkyard and now my car has a low volume very low note growl from the exhaust when I give it the boot.

And I guess the fact that the car's chip tuned means that I'll hear more air flow than I would otherwise.

I'd speculate that it sounds different though not "better" or "worse". But different from what you're used to. Nothing to worry about. I'll bet if, in a couple of years, you installed an identical muffler to the old one you would think it sounded "off" because you would be used to the MagnaFlo.

So yes, a non-issue I'm sure.

Dan