Is my cat-back after market?

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goonie
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Is my cat-back after market?

Postby goonie » Thu Jul 26, 2012 1:20 am

Hi All,

Just wondering if anyone can tell from these (not so great) pics that my mid pipe is after-market.

From googling around, I'm pretty sure that my muffler is not stock from comparing pics of other stock exhausts.

Image

This next pic shows whereabouts the hotdog is

Image

This next pic is a closer shot of the hotdog (scratched up from speed humps :x )

Image

It appears that its connected by fitting inside the other pipes, which would mean the diameter is smaller here? Is that normal?

The reason I am asking is all this is that I am contemplating whether I need a cat-back or not. Deep down, I am hoping this is a sufficient system (unlikey though) so I can upgrade extractors and cat only.

My MX5 is a 1990 Eunos Roadster NA6. The exhaust tip is 2 inches in diameter, if that helps with anything. Hopefully I'll try to get my hands on some calipers and measure the piping.

Thanks for looking

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NitroDann
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Re: Is my cat-back after market?

Postby NitroDann » Thu Jul 26, 2012 1:39 am

Its not stock from what I can see, but whether you 'need' to upgrade it depends on how much you will spend per kilowatt gained.

many will spend 1000 bucks on a second hand shiny droney HeKtiK JDM exhaust that adds little or nothing (under 5whp peak). Because what they want is to be able to tell mates that it has a full JDM exhaust, they dont actually care about performance at all, its all about the wank.

Decide what you want, tell us what the size is, and mandrel bent or not (doesnt look like it) and if the muffler is straight through or chambered, then I can tell you what if any difference it has or will make to performance and what/if a front pipe/extractors will help and by how much if you keep it.

Dann

Edit: Only just realized who you were haha
http://www.NitroDann.com

speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

project.r.racing
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Re: Is my cat-back after market?

Postby project.r.racing » Thu Jul 26, 2012 3:31 pm

Looks like a axle back exhaust to me.

project.r.racing
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Re: Is my cat-back after market?

Postby project.r.racing » Thu Jul 26, 2012 3:32 pm

Looks like a axle back exhaust to me, there is a weld and a pipe diameter change just after the resinator.

goonie
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Re: Is my cat-back after market?

Postby goonie » Thu Jul 26, 2012 5:07 pm

Dann, I can't answer any of those questions haha.

I'll pm you later...

With the resonator, the pics don't show the other side of it but I am 99% sure that the piping is the same size as the pipe shown. Looks like the diameter change on either side of the resonator was to make it fit (a proper exhaust would keep the same diameter right?).

Guess I'm trying to figure out the motive behind the replacement of the exhaust, whether it was for performance or maintenence reasons.

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zossy1
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Re: Is my cat-back after market?

Postby zossy1 » Thu Jul 26, 2012 6:47 pm

NitroDann wrote:its all about the wank.


I just lol'd :)

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NitroDann
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Re: Is my cat-back after market?

Postby NitroDann » Thu Jul 26, 2012 6:54 pm

project.r.racing wrote:Looks like a axle back exhaust to me, there is a weld and a pipe diameter change just after the resinator.



I can see that but that resonator isnt stock, and its welds arent stock welds.

Perhaps it has a straight through muffler and then someone added a hotdog resonator to quieten it down again.

So it may have a stock midpipe with a resonator or it may be completely changed.

Dann
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speed wrote:If I was to do it again, I wouldn't even consider the supercharger.

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Re: Is my cat-back after market?

Postby Captain Scarlet » Thu Jul 26, 2012 9:10 pm

What does exhaust sound like? I do think looks like exhaust shop job to keep car going. tee hee hee. Perhaps grandparents repair exhaust for young girl so not to scare dog. No intention to release horses. Big tip means nothing. what behind tip important.

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