NA6 extractors, exhaust and intake recommendations

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twr7cx
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NA6 extractors, exhaust and intake recommendations

Postby twr7cx » Tue Nov 28, 2017 8:31 pm

I'm sure this would have been discussed before. Probably many times. But the search is giving me nothing so hopefully someone won't mind repeating the answer or providing a URL for previous discussion.

Have a 89 NA6. I'm interested in seeing if I can get just a little bit more out of it - would a set of extractors and freer flowing exhaust system assist? If so, any tried and proved brands (I've seen Hurricane advertised?) and sizes (2.25"?)? Anything to be gained from the air intake?

Thanks.

3gress
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Re: NA6 extractors, exhaust and intake recommendations

Postby 3gress » Wed Nov 29, 2017 2:57 am

There are gains, albeit minor, to be had by freeing up the intake and exhaust flow.
Portmatching the manifolds to the head and increasing exhaust pipe diameter can result in a few added ponies though don't be expecting huge gains. It is wise to look at the whole system, a set of decent headers such as fujitsubo or racing beat, free flowing cat and cat back system will make a dicernable improvement.
Cleaning up the intake and exhaust ports by removing the casting dags and smoothing the bifurcation edge between valve ports can help. It is not a great idea to polish the intake side as the general theory is to leave the port surface rough. Stepping a bit beyond your query there though.
On the intake side of things probably the best idea is to make sure it is fed with fresh cool air.
Heaps of info on cowl fed intakes and such can be found across the net.

I have a fujitsubo catback recently purchased second hand that i may consider selling if you were interested.
This system is designed for increased flow while keeping the noise sedate enough to not cause problems.
I believe 949 racing still offers the fujitsubo rm01a catback system that is designed for all out warfare with the higher decibel volume to boot.

twr7cx
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Re: NA6 extractors, exhaust and intake recommendations

Postby twr7cx » Fri Dec 01, 2017 10:01 am

There doesn't seem to be a huge amount of off the shelf cat back exhaust systems available for the NA6. So far Ive found the Magnaflow 15715 < http://www.magnaflow.com/products?partN ... levehicles > and Xforce ES-MX-01 < http://www.xforce.com.au/xforce-product ... 3/vid-4849 >. A fair price difference between the two - Magnaflow seem to be around $1,1000.00ish and the Xforce only $600.00.

What suprises me is that both exhaust systems are stainless steel1?! I would have thought the aim for the MX5 would be to keep weight down so mild steel would have been lighter?

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Re: NA6 extractors, exhaust and intake recommendations

Postby NitroDann » Fri Dec 01, 2017 10:31 am

Both materials are near identical density.
http://www.NitroDann.com

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

3gress
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Re: NA6 extractors, exhaust and intake recommendations

Postby 3gress » Fri Dec 01, 2017 7:18 pm

Apart from weight and material longevity mild steel always seems to give a more mellow exhaust tone whereas stainless gives a raspy note.
If you have no issues with ordering from overseas rev9 have a few catback systems on offer.
Fujitsubo legalis would be my pick for the sound. Available in mild steel midpipe/stainless muffler or complete stainless system. If i had the cash I'd go straight for the fuji RM01A stainless system from 949 Racing as it is just freaking awesome..lightweight and designed for maximum flow.

I have ran a legalis system on my Astina and it made beautiful noises without drone or defect attracting decibels.

Not fishing but again i have a spare catback fujitsubo legalis mild steel/stainless used system in decent condition if O.P. is interested.

93_Clubman
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Re: NA6 extractors, exhaust and intake recommendations

Postby 93_Clubman » Sat Dec 02, 2017 11:20 am

Re catback exhaust, Town & Country in Geelong Vic do one that's popular - may be they'll ship it to you to be fitted locally. Expect they could also supply a high flow cat as well, but not sure if they will have extractors & primary pipe, although they could recommend &/or obtain for you to supply a complete system. Re CAI, MX5 Mania or Loch Stewart type (including DIY variants) are the most common.

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Re: NA6 extractors, exhaust and intake recommendations

Postby wasp47 » Sat Dec 02, 2017 11:28 am

Research the cowl fed CAI, you can make it yourself for bugger all. I couldn't stand the noise in the cabin though :NA6: :idea:

twr7cx
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Re: NA6 extractors, exhaust and intake recommendations

Postby twr7cx » Wed Dec 13, 2017 12:29 pm

Thanks all for the replies. I’ve sorted out a cold air intake with the parts of the cowl induction ordered and on their way to me.

There’s lots of good condition used extractors available to suit the NA6 so going to snap up a set and a generic high flow cat converter to be fitted.

The XForce ES-MX5-01 Cat Back Stainless Steel System < http://www.xforce.com.au/xforce-product ... 3/vid-4849 > seems to be the best priced brand new exhaust system at $600.00 but when I contacted them they advised that it is 2.5” which seems to be excessively big for a 1600cc motor.
I’ll investigate the Town and Country option.

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shirtz
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Re: NA6 extractors, exhaust and intake recommendations

Postby shirtz » Thu Dec 14, 2017 4:27 pm

let me know how you go. id be interested in a exhaust. sound files is a must please :)

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Re: NA6 extractors, exhaust and intake recommendations

Postby trader » Sat Dec 30, 2017 1:19 pm

Have a listen to the cobalt exhaust on line. I have had one on my 1.6 for years now and find it great - not too loud and no drone - may be expensive to purchase from US now though.
NB SE, NA 1.8.


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