Ok to extend exhaust?

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kman82
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Fri Dec 17, 2010 2:43 pm

My car's currently in the bodyshop having a full respray and tech 2 fitted. The car is a prefacelift cabby '88 and has what appears to be a part stainless exhaust system.

The problem we're having is that the old exhaust isn't long enough to clear the new tech 2 bumper....

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The bodyshop have offered to extend the exhaust on the straight section before the back box by welding in a couple of sections of tube they have lying around.

I've no idea what the other options are here if there are any! Is it ok to extend an exhaust like that?

cheers
Speedtouch
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Fri Dec 17, 2010 3:03 pm

It should be OK to extend it be 2 or 3 inches without ill effect, so long as the extension sections are of similar material to the existing stainless.
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kman82
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Fri Dec 17, 2010 3:16 pm

I'm not entirely sure it is all stainless to be honest. Its only the tailpipes that are shiney.

They would only be extending it by about 3 inches just to clear the bumper. He's going to adapt the bracket too so that it sits central to the hole
kman82
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Sun Dec 26, 2010 11:25 pm

so do pre facelift and facelift e30's have different length exhausts?
cecotto479
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Mon Dec 27, 2010 9:26 am

kman82 wrote:My car's currently in the bodyshop having a full respray and tech 2 fitted. The car is a prefacelift cabby '88 ..........

I've no idea what the other options..........
Stopping the whole process and not ruining another pre facelift cab?
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StuBeeDoo
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Mon Dec 27, 2010 9:41 am

kman82 wrote:so do pre facelift and facelift e30's have different length exhausts?
Not sure about the length, but the tailpipes are swan-necked on the facelifts whereas pre-facelift ones are straight.
This is why I no longer drive an E30......

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HairyScreech
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Mon Dec 27, 2010 2:01 pm

extending it by a few inches after the gas has gone through two silencer boxes will have naff all effect.
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leeparkes
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Mon Dec 27, 2010 2:08 pm

Id extend the tailpipes, custom exhaust place should be able to sort this...
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mrLEE30
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Mon Dec 27, 2010 3:18 pm

why bother with welding ect, just get some of the chrome extension paieces as found in almost and car accessory shop, fit them and cut down the fitting screws. if you dont want chrome then sand and paint em black.

this is what i did on mine, although in the pics i had not yet cut down the mounting screws so they are visible.

and as for the effect as you will well know these exhaust tips will add upto 50hp onto your car :eek:

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brooklynballer
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Mon Dec 27, 2010 4:13 pm

mrLEE30 wrote:why bother with welding ect, just get some of the chrome extension paieces as found in almost and car accessory shop, fit them and cut down the fitting screws. if you dont want chrome then sand and paint em black.

this is what i did on mine, although in the pics i had not yet cut down the mounting screws so they are visible.

and as for the effect as you will well know these exhaust tips will add upto 50hp onto your car :eek:

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Mon Dec 27, 2010 4:19 pm

brooklynballer wrote:
No offence but your rear light have got to be the worst lights iv ever seen

Ahahaha. No offense but... Ahaha, only ever gonna be offensive. :D
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brooklynballer
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Mon Dec 27, 2010 4:21 pm

Jim320i wrote:
brooklynballer wrote:
No offence but your rear light have got to be the worst lights iv ever seen

Ahahaha. No offense but... Ahaha, only ever gonna be offensive. :D
Ino but might make him feel better
kman82
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Mon Dec 27, 2010 7:59 pm

Thanks all,
HairyScreech wrote:extending it by a few inches after the gas has gone through two silencer boxes will have naff all effect.
We had discussed extended it before the last silencer box so that the polished tail pipes would remain unmolested. If we extend it in this middle section will that make much difference? What are the effects? Loss of power? noise?

If its going to have major consequences i might go down the screw on bits temporarily until i can take it to a specialist.
e30topless
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Mon Dec 27, 2010 8:03 pm

why not just fit the right exhaust ?
kman82
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Mon Dec 27, 2010 8:05 pm

e30topless wrote:why not just fit the right exhaust ?
Lack of funds i'm afraid pal.

I hate cutting corners and will eventually have the right exhaust but i've spent so much on the re-respray it will have to wait for now
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