new exhaust no back box ???

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D n D & K
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new exhaust no back box ???

Post by D n D & K » Tue Nov 04, 2008 8:17 pm

hello all

just been looking through a few posts using the search as we need to replace the back box

to my supprise i noticed a post about not having a back box just replace it with pipe

my questions are
is this legal ( is it not noisey )?
does it not effect performance, back pressure etc ?
scanner
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Re: new exhaust no back box ???

Post by scanner » Tue Nov 04, 2008 8:30 pm

D n D & K wrote:hello all

just been looking through a few posts using the search as we need to replace the back box

to my supprise i noticed a post about not having a back box just replace it with pipe

my questions are
is this legal ( is it not noisey )?
does it not effect performance, back pressure etc ?
No it's not noisy (certainly not 500bhp 1.0 litre Saxo/Corsa noisy) as the turbo has absorbed a lot of the energy and the first box absorbs most of the rest.

Those who have run without one for a while reckon the Bongo goes better without the back pressure strangling it.

My other car (also a Turbo Diesel) has a big hole in the catalytic convertor at the moment - at 120,000 miles it now goes better than it ever has done
and is very little noisier than it used to be. I shall be replacing the cat with a piece of flexi before the next MOT.

PS - The cat isn't needed for the MOT either.
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Re: new exhaust no back box ???

Post by bigdaddycain » Tue Nov 04, 2008 8:46 pm

Won't the engine management light illuminate with the cat removed ?
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ford tinny

Re: new exhaust no back box ???

Post by ford tinny » Tue Nov 04, 2008 8:54 pm

Hello,
Yes Vanvliet has a stainless flexi pipe instead of a back box (no problems)
Image

I also have done this with my middle flexi pipe and box, works a treat

Image

Image

Thanks John
Last edited by ford tinny on Tue Nov 04, 2008 9:04 pm, edited 1 time in total.
bigdaddycain
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Re: new exhaust no back box ???

Post by bigdaddycain » Tue Nov 04, 2008 9:00 pm

Nice looking job john :wink:
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D n D & K
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Re: new exhaust no back box ???

Post by D n D & K » Tue Nov 04, 2008 9:05 pm

so you have no boxes at all on yours and it passes mot ?
ford tinny

Re: new exhaust no back box ???

Post by ford tinny » Tue Nov 04, 2008 9:09 pm

Hello,
First picture is Vanvliet's Bongo with no back box and the two other pictures are of my middle flexi on my Freda

Thanks John
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Re: new exhaust no back box ???

Post by D n D & K » Tue Nov 04, 2008 9:12 pm

o i see thanks
cheffy34
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Re: new exhaust no back box ???

Post by cheffy34 » Tue Nov 04, 2008 11:33 pm

bigdaddycain wrote:Won't the engine management light illuminate with the cat removed ?


I'd have thought something would light up on the dash, plus i thought it was illegal on cars built after 92 j/k plate :?: surely it would play havoc with fuelling and emissions aswell :?:
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scanner
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Re: new exhaust no back box ???

Post by scanner » Tue Nov 04, 2008 11:46 pm

bigdaddycain wrote:Won't the engine management light illuminate with the cat removed ?
Nope - it's not a petrol so no electrical connection (lambda sensor or whatever) that I'm aware of.

It's non electronic injection (like the Bongo), it has an ECU but no electronic control of injection.
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Re: new exhaust no back box ???

Post by scanner » Tue Nov 04, 2008 11:52 pm

cheffy34 wrote:
bigdaddycain wrote:Won't the engine management light illuminate with the cat removed ?


I'd have thought something would light up on the dash, plus i thought it was illegal on cars built after 92 j/k plate :?: surely it would play havoc with fuelling and emissions aswell :?:
It's not a petrol, so not an issue.

I've been reliably informed that diesels only have to have things like EGR and a cat to be sold, once sold it appears they are no longer checked - decat pipes for tuned diesels are a common mod - either that or just smashing the core out with a hammer and big screwdriver.
cheffy34
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Re: new exhaust no back box ???

Post by cheffy34 » Wed Nov 05, 2008 12:02 am

Ahhh :!: thanks scanner :wink: never had a diesal :oops: did borrow one once tho :roll: :lol:
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scanner
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Re: new exhaust no back box ???

Post by scanner » Wed Nov 05, 2008 1:18 am

cheffy34 wrote:Ahhh :!: thanks scanner :wink: never had a diesal :oops: did borrow one once tho :roll: :lol:
You have experienced the future once then?
bigdaddycain
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Re: new exhaust no back box ???

Post by bigdaddycain » Wed Nov 05, 2008 6:09 pm

scanner wrote:
bigdaddycain wrote:Won't the engine management light illuminate with the cat removed ?
Nope - it's not a petrol so no electrical connection (lambda sensor or whatever) that I'm aware of.

It's non electronic injection (like the Bongo), it has an ECU but no electronic control of injection.
Right... i'm with ya. :wink:
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vanvliet
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Re: new exhaust no back box ???

Post by vanvliet » Fri Nov 07, 2008 11:56 am

Mine has been without a box on the rear for about a year and a half. ( stainless flexi and chrome tailpipe) Works fine for me /have not had to maintain it in any way and I have never had any comments about it being loud .I swear that is a bit nippier on acceleration too If it falls off tomorrow I would not fit another rear box. The van has Passed MOT no problem :D
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