Why does S54 M3's sound like shit with exhaust mods?

[M powered]

I am getting my exhaust installed tomorrow. Will I encounter the same problem?

My friends boss M3 sounds like a metallic rattle with the exhaust mod. The exhaust is a custom magnaflow. Its a straight through design.

I've heard the same exhaust on many different cars, they all sound good. But for some reason they sound like a tin can with the M3.

Will this happen to me?

[V Shah]

It is very likely that the metallic sound is coming from the headers. There are also rumors that it's the engine itself.

[M powered]

Originally posted by V Shah
It is very likely that the metallic sound is coming from the headers. There are also rumors that it's the engine itself.

So no matter what exhaust you buy, its still going to sound like a tin can?

[V Shah]

I have heard the ACS and the Eisenmann exhaust for the M3 and although they are both deeper and louder, then still have the metallic characteristic. So I suppose the answer to your question is yes.

[SDbboy]

The problem lies with the resonator box, once removed it sounds nice, even stock.

Brian

[M powered]

Originally posted by dallasbboy
The problem lies with the resonator box, once removed it sounds nice, even stock.

Brian

No it doesnt, the M3 had the resonator box removed, still sounds like a tin can. Its worst with the resonator box in.

[SDbboy]

I thought that would solve it, maybe its the Vanos?

Brian

Originally posted by M powered


No it doesnt, the M3 had the resonator box removed, still sounds like a tin can. Its worst with the resonator box in.

[Dark Helmet]

vanos wouldn't do too much, maybe some... unless it is advancing the cam timing so much that the valve is closing before combustion is complete? or maybe its too far retarded and the resonance is created by the valves opening to late.....

is the firing order the same in the S54 as the S52?

also, it could be the crank angles (don't knwo how) a "flat crank" ferrari F360 sounds nothing like a traditional 90-degree crank... but that is with multiple cylinder banks, so it may not be of any relevance.

the other thing that could be at work is the header and the order in which the primaries come together vs. the firing order... I know that with SB Fords, there are distinctly different exhaust tones between log-type manifolds, a tri-Y header, unequal-length shorties, equal-length shorties, and long-tubes... each has its own sound and it relatively distict.

I'll put my money on the header design. It actually sounds plausible that that is the cause.

if you ask me it kind of sounds like half a ferrari V12...

[Dark Helmet]

AND in SB Fords, the sound is different from 289/302 firing order to 351/5.0 firing order.

[SilverStreak]

I heard a Laguna Seca Blue M Coupe go by a few mos ago (I mention the color cuz I know it was an S54) and he clearly did not have the stock exhaust system on there, yet it sounded very cool. No metallic rasp to it at all, sounded very tuned, yet a low rumble, I wish I knew what he was running. But his 4 exhaust tips were angled slightly up, if that helps at all...

[V Shah]

I know supersprint makes a DTM style exhaust for the coupe but it could just have easily been something custom.

[SilverStreak]

Could be it, yeah! It sounded and looked fantastic!

[bimmerpwr]

My Super Sprint sounds awesome after engine is warmed up. When I first start the car, metallic sound is very apparent for a moment. But once the car is warmed up, there is no more annoying metallic sound and only deep growl can be heard. Pretty cool actually.
I had my doubts before I got Super Sprint but it is well worth while. You gotta hear it when you accelerate hard in 1st gear up to 7k and just slow down without braking. Gives a big smile for sure.

[SilverStreak]

I bet you SuperSprint was the one then...

[chazzy]

What exhaust was on there? Some exhausts (Kelleners comes to mind) on the S54 make it sound like a really loud chainsaw ripping through sheet metal. Some people like it, some don't. The sound is very distinctive. Some exhausts can mask the sound better than others, but the sound is probably caused by backpressure in the system, which is just a characteristic of the engine. I've grown to like it a lot.

[SDbboy]

Could have been Eisenmann, they sound better on S54s but still a bit of the chainsaw is there even with the racing version.

Brian