BX19D exhaust

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white exec
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BX19D exhaust

Post by white exec »

Engine running well, but not entirely happy with the level of noise from the exhaust.

At idle, the noise from the tailpipe is quite burpy (sounds almost leaky, but isn't) and putting a hand near the tailpipe you can feel every single pressure wave coming down the pipe - a smoothed (quiet) stream of gases it isn't!

Almost certainly an aftermarket system, but not leaking, and looks very sound. Consists just of one long front pipe, and the two rear boxes. Just wondering whether it's pretty-much "straight-though", and a bit lacking in the baffle department.

Reading old posts, looks as if Bosal is a preferred system (OE on many models), and have used them for years...
Bosal system.JPG

What I'd like to achieve is extra quietness, particularly at motorway speeds (and at idle!).
Should the Bosal system do better?
I see that my exhaust manifold has the lower blanking plate in place, presumably for the 1.7D "pot" resonator.
Is there any advantage in fitting the resonator? Would it quieten things further, or add a complication?

Would it be worth looking at the TD rear boxes, bearing in mind I might have to re-use my existing front pipe?

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Re: BX19D exhaust

Post by Jaba »

I have never found the Bosal systems, on a GTi at any rate, any quieter. Walker was the only one that sounded quieter.
If you check out the TD exhaust you will see that it is different and has different ball and socket connections rather than a clamped pipe on a spigot.The major difference is the middle box as this is larger and might absorb more sound. The tailboxes are straight through and have glassfibre packing for sound absorption.I think the petrol 1600 and 1900 systems are the same as yours.
No easy way to convert one to the other unless the long front downpipe is the same diameter.
Exhaust noise in practice is not a noise nuisance at speed as the road and wind noise drown out even the engine noise. On my petrol GTi there is an annoying exhaust resonance of increased noise from 55 to 65 but you just learn to live with it as it would take extraordinary sound deadening measures to the car interior to mask this.
The Joy of BX with just one Citroën BX to my name now. Will I sing Bye Bye to my GTI or will it be Till death us do part.

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Tim Leech
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Re: BX19D exhaust

Post by Tim Leech »

They do sound like that a bit, if its running smooth I would leave it be, if its noisy inside the car check you have no holes or seal letting sound in.
Lots of Motors, mostly semi broken....