NA6 vs NA8 exhaust

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GS
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NA6 vs NA8 exhaust

Postby GS » Fri Jul 09, 2010 11:30 am

Hi
Does someone know what the difference is between the exhausts on the NA6 and NA8 (or indeed, if there is a difference)? I thought I read years ago that there was a difference, but I haven’t been able to find that information.

My understanding was that the cat converter was located further upstream or downstream on the NA8? Is that right? Obviously the exhaust ports on the 1.8 are different, so im talking about the rest of the system after the headers.

It gets a bit confusing because some places list separate cat back exhausts for the 1989-93 and 1993-97 model years, but others just lump them all together.

The reason I ask is that a few weeks ago i picked up a stainless steel exhaust for my NA6 from a wreckers. They just said it was for any NA, but I have a feeling it was from a NA8 (I think they were stripping Locutus’s old car at the time??). I bought it knowing I would probably have to get an exhaust shop to adapt it for my car, but as I got it for a good price im hoping its a worthwhile exercise.

Thanks
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Guran
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Re: NA6 vs NA8 exhaust

Postby Guran » Fri Jul 09, 2010 1:00 pm

Standard NA8 cat back exhaust fits an NA6, no problem. There may be some slight differences in heat shields but nothing significant. Only takes an hour or so to swap them over so I imagine you'll find out for yourself this weekend.
Standard 2006 NC - YouTube
WP 1:11.89 | SMP-S 1:05.90 GP 1:54.93 N 1:18.09 L 2:22.49 | PW 1:02.52
PI 2:00.55 | W-S 1:12.44 W-L 1:43.36 | SR 1:33.25

93_Clubman
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Re: NA6 vs NA8 exhaust

Postby 93_Clubman » Fri Jul 09, 2010 1:16 pm

na6 was 1 7/8 inch diameter v 2 inch (from memory) for na8.

trying to remember the differences between my old na6 & my na8, although my current setup is aftermarket it was standard when na8 first purchased - another difference might have been the bullet shaped muffler/ resonator near the rear wheels on the na6, which i don't think carried over to na8.

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Re: NA6 vs NA8 exhaust

Postby Guran » Fri Jul 09, 2010 3:32 pm

Hmmm, are you sure about that? Opinion at miata.net suggests that NA6 and NA8 catback exhausts are the same with the exception of an O2 sensor in late model NA8s.

http://forum.miata.net/vb/showthread.php?t=274721
Standard 2006 NC - YouTube
WP 1:11.89 | SMP-S 1:05.90 GP 1:54.93 N 1:18.09 L 2:22.49 | PW 1:02.52
PI 2:00.55 | W-S 1:12.44 W-L 1:43.36 | SR 1:33.25

93_Clubman
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Re: NA6 vs NA8 exhaust

Postby 93_Clubman » Fri Jul 09, 2010 6:02 pm

As stated it's from memory, & not saying it won't fit. Due to US emissions standards their cars might not be the best comparison on some aspects.

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GS
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Re: NA6 vs NA8 exhaust

Postby GS » Fri Jul 09, 2010 6:45 pm

Thanks guys.

Interesting. Maybe i was getting confused and thinking of the exhaust differences between NA vs NB.

If this exhaust just bolts on, then thats even better.

It would be nice to think i could get it done in an hour this weekend, but unfortunately its going to take longer than that as i plan on pulling the turbo gear off my car at the same time. Plus the house renos should probably be completed first.
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Guran
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Re: NA6 vs NA8 exhaust

Postby Guran » Fri Jul 09, 2010 10:37 pm

93_Clubman wrote:As stated it's from memory, & not saying it won't fit. Due to US emissions standards their cars might not be the best comparison on some aspects.

Fair enough. 8)
Standard 2006 NC - YouTube
WP 1:11.89 | SMP-S 1:05.90 GP 1:54.93 N 1:18.09 L 2:22.49 | PW 1:02.52
PI 2:00.55 | W-S 1:12.44 W-L 1:43.36 | SR 1:33.25

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Re: NA6 vs NA8 exhaust

Postby Smithy » Mon Jul 26, 2010 12:30 pm

Don't suppose you've had a crack at fitting that exhaust yet ?

I know how house renovation can "interfere" with other plans :wink:
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GS
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Re: NA6 vs NA8 exhaust

Postby GS » Mon Jul 26, 2010 6:40 pm

No, havent had the time yet :frown:

Finishing off the kitchen at the moment. Id pick working on my car over cutting/trimming polyurethane kitchen cover panels anyday. Man that stuff is fiddly...
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