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new exhaust no back box ???
Posted: Tue Nov 04, 2008 8:17 pm
by D n D & K
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 ?
Re: new exhaust no back box ???
Posted: Tue Nov 04, 2008 8:30 pm
by scanner
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.
Re: new exhaust no back box ???
Posted: Tue Nov 04, 2008 8:46 pm
by bigdaddycain
Won't the engine management light illuminate with the cat removed ?
Re: new exhaust no back box ???
Posted: Tue Nov 04, 2008 8:54 pm
by ford tinny
Hello,
Yes Vanvliet has a stainless flexi pipe instead of a back box (no problems)
I also have done this with my middle flexi pipe and box, works a treat
Thanks John
Re: new exhaust no back box ???
Posted: Tue Nov 04, 2008 9:00 pm
by bigdaddycain
Nice looking job john

Re: new exhaust no back box ???
Posted: Tue Nov 04, 2008 9:05 pm
by D n D & K
so you have no boxes at all on yours and it passes mot ?
Re: new exhaust no back box ???
Posted: Tue Nov 04, 2008 9:09 pm
by ford tinny
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
Re: new exhaust no back box ???
Posted: Tue Nov 04, 2008 9:12 pm
by D n D & K
o i see thanks
Re: new exhaust no back box ???
Posted: Tue Nov 04, 2008 11:33 pm
by cheffy34
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

Re: new exhaust no back box ???
Posted: Tue Nov 04, 2008 11:46 pm
by scanner
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.
Re: new exhaust no back box ???
Posted: Tue Nov 04, 2008 11:52 pm
by scanner
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.
Re: new exhaust no back box ???
Posted: Wed Nov 05, 2008 12:02 am
by cheffy34
Ahhh

thanks scanner

never had a diesal

did borrow one once tho

Re: new exhaust no back box ???
Posted: Wed Nov 05, 2008 1:18 am
by scanner
cheffy34 wrote:Ahhh

thanks scanner

never had a diesal

did borrow one once tho

You have experienced the future once then?
Re: new exhaust no back box ???
Posted: Wed Nov 05, 2008 6:09 pm
by bigdaddycain
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.

Re: new exhaust no back box ???
Posted: Fri Nov 07, 2008 11:56 am
by vanvliet
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
