Exhaust Noise

[tkdsteve08]

Hi All

Strange question for you

Just brought a new mongoose cat back exhaust system for the ATR. When you first start driving the car form cold it's really quiet, but after half an hour it sounds great (Much louder.)

Any Idears peeps.

[PJ S]

Yes, speak in a more befitting manner - no such thing as idears, and you bought, not brought!

In regards to the exhaust unit, I've no idea as to why it's behaving as you explain, other than heat expansion of the metal, causing a mild resonance which is boosting the sound pressure level.
If that's not the reason for it, then I'm at a loss as to what else is at play.
Perhaps speak with Mongoose themselves, see if they know why this is happening.

Is the increase in noise level creating untoward effects - in-car droning, abuse from neighbours, making you concerned about being stopped by the police, etc?
If not, and the tone doesn't change, then I wouldn't worry about it.

[tkdsteve08]

Thanks pj's

I wlii wokr on my spelling.

The car does have a slight leak from the down pipe, and I am wondering if the exhaust is heating up and sealing that hole, so letting more air threw the back boxes.

What are your thoughts.

[PJ S]

My thoughts are as before - and may be correct or wide of the mark, I honestly don't know.
I'd sort out the leaky downpipe if for no other reason than it needs done.
See if that changes things - if not, then it's something else.

[300bhp/ton]

tkdsteve08 said:

Thanks pj's

I wlii wokr on my spelling.

The car does have a slight leak from the down pipe, and I am wondering if the exhaust is heating up and sealing that hole, so letting more air threw the back boxes.

What are your thoughts.

Or it's the downpipe you are hearing more as it's warmed up and expanded?

[Shinobi]

Not an expert of Honda's by any means but don't most exhausts get louder after warming up? I know that the Evo's and 350z that I've owned have both sounded very different and louder after a good motorway run. I always assumed it was due to the metal expanding under heat.

I would definatly reccomend getting the downpipe fixed though as the loss of back pressure isnt going to do you any favours.

[JayK12]

Is your downpipe blowing at the flexi? Common problem.
Wouldnt worry about it. It carbon's up and usually the note is the same hot or cold, the fact that you cannot engage VTEC when its cold, how can you compare?

Get downpipe fixed and dont worry about it.