Exhaust boom at 1800 revs on 330

[cis121]

Hi,

I've only got the car a month ago and there is a queit booming sound in the exhaust at about 1800 revs when accelerating. It's fairly quiet, but other than that, there is no other exhaust noise whilst acelerating.

Do you any of you folks get a similar resonance at these revs or do my exhaust baffles sound on the way out?

[Dino D]

I think the 'booming' you refer to is just the great sound of the engine unless it is the diesel.

The petrol one I had had lovely bassy note at about that rev. The engine note is of the best things about that car!!

[blackspider]

The 330 has a great bass note at low rpm.

We rarely get any faults in the exhaust system...I would say your baffles are likely to be Ok

[Andrew D]

I don't know if it'll be present on the E46, but on the E85 3.0i there's a very satisfying bass reverberation on the overrun in the lower gears, especially if you come off the gas sharply in sport mode. It sounds very motorsport-esque.

[blackspider]

Andrew D said:

I don't know if it'll be present on the E46, but on the E85 3.0i there's a very satisfying bass reverberation on the overrun in the lower gears, especially if you come off the gas sharply in sport mode. It sounds very motorsport-esque.

Sounds even better if you've had the engine sound package fitted-the sound from the air intake is sent to the baulk head

[Dunk76]

Do the 3.0 engines have the exhaust resonance flap as per the 2.8 engines?

The flap was stuck open on the Alpina - and the resonance between 2000 and 2500rpm was unbearable.

A smack with a 3" Adjuster (hammer) sorted it out, and made the whole cruising thing much more bearable.

[Dino D]

blackspider said:

Sounds even better if you've had the engine sound package fitted-the sound from the air intake is sent to the baulk head

You've just explained something I could never understand about my one: I test drove 3 330i sports. Two were the pre-facelift and the final one was the 2002 facelift model.

The 2002 one had such a great sound compared to the others that after the test drive I asked for the air-box to be checked for an aftermarket filter. It was standard. Needless to say my judgement was clouded and I had decided to buy it the minute I first heard that induction growl. The grey interior, crappy wood trim and business radio were a worthwile compromise for that gorgeous sound. It really was one of those cars that I would leave the stereo turned down just to hear the engine!

It was a perfect blend of bass from the exhaust at low revs coupled with a gruff, harder edged growl at high revs. For the first time in my life my wife didn't complain when I opened the taps! In fact, when she went for a spin in an M3 she actually thouth it was broken when she heard the shrill shriek coming from that engine!

What do they do to let in more of that induction grow? I always suspected mine had less sound deadening material in the firewall-like the 330i Club Sport Coupes?