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Hi !

I've just bought a 99 NB 1.8 5 speed and want to put a full exhaust system on it. I've been quoted $1,800 from a MX-5 specialist in Melb which seems quite high ! I've read through other postings and most people seem quite happy with the N Power extractors off e-bay which I could team with one of their Magnaflow hiflow cats. My main concern is that these are 2.5 inch, is that a bit big for a 1.8 ? Should I be looking for extractors & a cat that are 2.25 inch ?

Any suggestions would be greatly appreciated Are their any other brands of extractors I should be considering ?

regards,

toymx5

I actually haven't heard anything about the N*power extracters but the mufflers are quite popular.

N Power header & rear muffler is a copy or Racing Beat. Since your car is 99 I think it should be ok. People with 6 speed (NB8B) had some issue with eBay headers, the pipe hit their gearbox.

$1800 for full system is actually ok if you get branded stuff. You can get it for a lot less if you get custom mid pipe & axle back muffler. A good quality Japanese header will set you back $1.3- $1.5 K, thats just the header!!!

2.5 cat is fine, as long you get a quality hi flow cat, the rest 2.25" will do just fine
viewtopic.php?f=44&t=35955

The npower muffler is good, but I wouldn't touch the headers, I will only go branded researched and developed headers.

We know that a Town and country (Geelong) high flow steel cat and sports system(built on the car) will give around 6-10 RWKw. for around $1000 and sound great.STEVESPORTS has such a system(see results at Vic Dyno day post in General chat)

Extractors on an NB are an improvement but not much and would add another $500 to the bill.

From my experience with RB and Xforce i would go withe the cheaper Xforce extractors.

Peter

pcmx5 wrote:Extractors on an NB are an improvement but not much and would add another $500 to the bill.

I'd agree. The factory NB headers look pretty good.

Aren't the NB8B headers better than the NB8A, one being tubular i think?

philz wrote:Aren't the NB8B headers better than the NB8A, one being tubular i think?

NB8a's are tubular unlike the cast jobbo's that come on NA8a's.I think that is the difference not NB8A/NB8B.

Peter

I'll pull the heat shield off tonight and have a look at the exhaust manifold and see if it's the good tubular one or not. If it is I might just get the Town & Country cat back system, I like the sounds of 6 - 10 RWKW !!

Thanks for all the comments, have been a big help

pcmx5 wrote:NB8a's are tubular unlike the cast jobbo's that come on NA8a's.I think that is the difference not NB8A/NB8B.

Peter

Only the yanks got cast headers on their early NBs.

Look at the Mania website, the "extended secondaries and high flow cat" is a good solution for the NB. A lot less time (and thus money) taken to fit it with almost the same gains as a set of full extractors.

toymx5 wrote:I'll pull the heat shield off tonight and have a look at the exhaust manifold and see if it's the good tubular one or not. If it is I might just get the Town & Country cat back system, I like the sounds of 6 - 10 RWKW !!

Thanks for all the comments, have been a big help

I can tell you it will be tubular unless someone for some reason has changed over to an NA8A one;i have a 98 manifold from Leon W's car sitting in my garage and it is tubular.

His car with a high flow cat(not steel, and it seems steel are better) and a T&C system made a gain of 6rwkw but the before run (early morning)was at 20deg and the after at 33 (late afternoon)which would have robbed some power.The dyno guys estimated 2kw.

Stevesports NA8B made a few more kw with a steel cat then another NB8B with just the exhaust on the same day so even allowing for individual differences there seemed to be value in using the steel cat.

Hope this helps,

Peter.

Okibi wrote:

pcmx5 wrote:NB8a's are tubular unlike the cast jobbo's that come on NA8a's.I think that is the difference not NB8A/NB8B.

Peter

Only the yanks got cast headers on their early NBs.

Look at the Mania website, the "extended secondaries and high flow cat" is a good solution for the NB. A lot less time (and thus money) taken to fit it with almost the same gains as a set of full extractors.

Is that why SMB only make secondaries?

pcmx5 wrote:
NB8a's are tubular unlike the cast jobbo's that come on NA8a's.I think that is the difference not NB8A/NB8B.

Peter

Whoops my bad, I remember asking the same question in another "headers" thread.

And I even pulled out the heatshield to have a look, and yes they are tubular (NB8A).

Sort of offtopic: Any downsides to removing a stock heatshield? The engine bay looks much better though.

Hi Okibi / Philz,

Are the extended secondaries a factory or aftermarket part ? I couldn't find anything on the mania site about them.

I had a look at my engine pipes and they are tubular, from what everyone has told me I'm thinking of getting the extended secondaries, a steel hi flow cat and system from Town & Country. This way the engine bay looks standard and I have a great note and more power

Once again thanks everyone for their help !!

Philz, Thanks so much for the photo, it's great, where did it come from ?

toymx5

Hey toy,

Site is http://www.smb.net.au/mx5zone.htm

If you do get extended secondaries, you will need something different to the above pictures, because the 99' has the cat in the mid pipe, whereas i believe the 01+ has cat in the secondaries as pictured.

Thanks Philz, I'll call SMB tomorrow and ask them about the secondary extension pipes and cat for the 99 and if they believe the 99 factory header pipes are as good as the 01's.

I'll let you know what they say !

toymx5