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Discussion Starter #1
Had a pro sport back box fitted. I aint happy with the noise it makes when ticking over/idling as it sounds as if the car is running lumpy/chugging. Had diagnostics done and al ok, revs are ticking over lower which is the norm I am told with a free flow back box etc. Is it just the way this type of back box is I wonder? If so I want a quieter one!!!

I am just wondering if 'lumpy/chugging' sound from the back box itself can be cured in anyway? I have contacted the fitter who said bring it back but its 60 miles away!! so any suggestions how I might be able to solve this? Its most noisy when the car is first started when cold.
 

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Any non-standard back box will make the exhaust pulses louder. Your lucky you didn't go for the Scorpion back box, sounds like a scooby in the mornings, in the afternoons, in the evening and on the motorway :hihi:rofl

Take it back and try some more wadding in the box but then it won't really be a free flow box. Plus i'm fairly sure you can't do anything to a free flow box to minimise the sounds because the pipe is straight through the silencer unlike normal silencers where it circulates the gasses through..

HTH :thumbsup
 

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Discussion Starter #8
ermm why chop the original box off and fit a pro sport box then?:confused:confused
Ermm because I wanted a twin pipe look and a better sound.

On a serious note understand the point you are making but when I asked it to be as quiet as possible and sound like the quiet hymm on there website and end up with something that's more like full sport it aint right. If I wanted the sound I have I would have gone for a scorpion exhaust.
 

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Discussion Starter #9
Update - Called the guys that fitted it, car booked in for next week. They plan to make it quieter by doing a back box with compartments rather than free flow to stop the idle popping/chugging. Will still sound better than the standard pea shooter just not so boy racer.
 
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