Author Topic: Exhaust pipe diameter question  (Read 1361 times)

Offline wellfan

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Exhaust pipe diameter question
« on: 05 April 2005, 20:10 »
I recently purchased a stainless steel back box for my 8 valver. I am planing to fit it this week, however, I have just noticed the diameter of the connecting pipe  from the back box is very wide compared to the other pipes in my system. It will need to be significantly squeezed to get it to clamp on to the centre box pipe. Could I have been given the wrong back box? What should the diameter of the connecting pipe be on an 8 valve and a 16 valve? I bought the back box, new, on ebay from a guy with great feedback and it has a printed label stating 8 valve on it. Any ideas how to fit it if it is the correct item

Veedubgt18v

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Re: Exhaust pipe diameter question
« Reply #1 on: 05 April 2005, 20:13 »
i think 8v exhaust is 2 inch bore and 16v exhaust is 2.5 inch bore you can probably get a reducer pipe from an exhaust centre to make it fit


Offline ...joe

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Re: Exhaust pipe diameter question
« Reply #2 on: 05 April 2005, 20:15 »
any stainless or performance exhaust will have a larger bore top spit the gasses out quicker so you'll have to get some reducer shims in there to make up the difference in diameter.
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Veedubgt18v

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Re: Exhaust pipe diameter question
« Reply #3 on: 05 April 2005, 20:16 »
joe shouldnt you be getting your car ready for inters............ :tongue:

Offline ...joe

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Re: Exhaust pipe diameter question
« Reply #4 on: 05 April 2005, 20:18 »
hey i get my head back tomorrow, just bought the downpipe...its getting there!!!




i hope!!!
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Veedubgt18v

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Re: Exhaust pipe diameter question
« Reply #5 on: 05 April 2005, 20:26 »
good luck man!

i got mot on thurs............... :undecided:

Offline wellfan

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Re: Exhaust pipe diameter question
« Reply #6 on: 05 April 2005, 21:07 »
Thanks for the replies, the bore is 2" so it must be the right one. Do I get shims at any exhaust fitting centre and what do I ask for?

Offline ...joe

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Re: Exhaust pipe diameter question
« Reply #7 on: 05 April 2005, 21:09 »
yeah take it in they'll know what to do, shouldn't cost much either.
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Offline wellfan

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Re: Exhaust pipe diameter question
« Reply #8 on: 05 April 2005, 21:24 »
gtijoe, will they be helpful if I am planning to fit the exhaust myself.

Offline ...joe

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Re: Exhaust pipe diameter question
« Reply #9 on: 05 April 2005, 21:53 »
yeah i fitted mine but it was blowing a bit so i got them to sort it out and it was fine, to them its just like doing a bit of a patch up job. in fact when i took mine in they all watched me drive off because they liked how it sounded!!!
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