NB8 headers fit onto NA8?

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NB8 headers fit onto NA8?

Postby sifoo » Wed Apr 11, 2012 7:34 pm

Hi guys,

My friend is thinking of giving me a great deal on his NB8 Maxim Works header. I was thinking of chopping the rear section (highlighted in red below) and welding a straight section on it to improve flow and to make it compatible with my NA8.

Would this work? Would I run into any other troubles?

Also, the EGR of the NB8 version is located on the first secondary whereas the EGR on the NA8 is located on the second secondary. Any issues there? Does the size of the EGR fitting work for both models?

Thanks for your help 8)
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Re: NB8 headers fit onto NA8?

Postby 93_Clubman » Thu Apr 12, 2012 1:09 pm

PCMX5 put NB8 headers on his NA8 & provides some info here:
viewtopic.php?f=29&t=28626&p=363121#p363121
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Re: NB8 headers fit onto NA8?

Postby sailaholic » Thu Apr 12, 2012 2:50 pm

I'm also doing this ( have the headers) but no cylinder head to fit them on. I've read the link and am a bit curious why there should be any clearance issues on the bell housing. I should be able to tell you in a few Weeks. Or you could tell me sooner!

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Top is apexi to suit na 8, NB maxim works, na8 stock.

I was going to avoid cutting them for resale purposes.

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Re: NB8 headers fit onto NA8?

Postby Okibi » Sun Apr 15, 2012 5:47 pm

I tried the other way around hoping there might be enough play to make it work.

I tried NA8 headers on my NB.

The fit around the bell housing but come further down the car than the NB headers so the flange for the cat is in the wrong place.

I have a set of titanium (I think) Mazdaspeed headers to suit an NA8 if someone has some NB headers they're looking to swap + - cash depending on what's out there.

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If you had access to a car like this, would you take it back right away? Neither would I.
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Re: NB8 headers fit onto NA8?

Postby sailaholic » Sun Apr 15, 2012 7:09 pm

Good top hear they fitted ok. Length to cat doesn't worry me as I'm getting a new cat put in anyway.

Highly doubt the ms ones are titanium I'm afraid. See plenty for sale in Japan and they never list them as titanium. Maybe you got a special version? Weight would tell you.

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Re: NB8 headers fit onto NA8?

Postby project.r.racing » Sun Apr 15, 2012 9:53 pm

aren't the flange bolt holes and bolts where the manifold attaches to the head in slightly different locations? or not?
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Re: NB8 headers fit onto NA8?

Postby sailaholic » Sun Apr 15, 2012 10:47 pm

Not , only on the intake side

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Re: NB8 headers fit onto NA8?

Postby sifoo » Mon Apr 16, 2012 12:43 am

Ditto to what Okibi said. I spoke to an exhaust shop and they say the only difference should be the length of the downpipe/flange to the cat. So If I'm chopping it and replacing it with a customised pipe, it should be no issue.

I'll let you guys know if I run into any trouble. Thanks for your help guys
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Re: NB8 headers fit onto NA8?

Postby sailaholic » Mon Apr 16, 2012 7:14 am

The NB will be too short, so you could just have a piece added that bolts between the existing exhuast and the headers. Alternatively, if you replace you cat get a generic weld in one and have them weld it into a pit of pipe the right length to make up the difference.
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