Just installed a cold air intake, 0 difference to induction noise?

Technical Area Engine, Transmission, Exhaust etc
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  1. My model of MX-5 is: 07
  2. I’m based near: NW LDN
  3. I’m looking for technical help or recommendations on: Induction sound

Just installed a cold air intake by Direnza (£215 on ebay but got for 170 with vouchers) hoping to get a nice induction sound to go with my straight midpipe, but i hear absolutely nothing, maybe during some acceleration id hear the slightest difference but overall it makes no difference to the sound, and i also had to remove the hood strut as it was in the way so not a good start, any reason for this? Or am i expecting too much, but even for a CAI you would expect lots more noise

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Try fitting without the heat shield (air box). You might have to fab up a bracket to support your mass air sensor without the airbox. If that makes a difference, then you need to leave the airbox, or modify it.. Of course, some would say you no longer have a “cold air induction”. Use one of those cheap outside temperature probes to measure befor and after, to see how much, if any, difference it makes.

Direnza air filter
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Why does my airbox look different?

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??

Looks the same

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Oh lol, im still confused as to why im not hearing much. When am i meant to hear it? When accelerating or? Btw any performance gains? I didnt buy it for performance but realistically it probs adds a horse or 2 lol, i DID notice more pops tho from my exhaust, maybe coz of the extra air?

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Generally when under WOT.

Youve basically replaced one airbox with another. The factory intake tubing is full of twists and turns called Helmholtz chambers which are designed to give a charge of air ensuring a smooth throttle response, but also quietening the throttle, to meet regulations.

Probably could have saved yourself £120, just fitting a universal cone filter

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Mx5 2.0 NC Air Box Mod
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Zip tie some intake ducting (old school is to use tumble dryer ducting from B&Q), from the mouth, through the bumper to the filter. Will probably create a venturi-like effect.

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On the NC these effectively make zero difference to sound or power. At least on the NA/NB you could achieve a nice induction howl.

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just realised ■■■■, looks cool at least but was hoping for a little more, maybe lowering springs next

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Adding these is an option for flow also.

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Cobalt air intake pipe , approx £70

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Where does it go?

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The silicon pipe replaced the plastic circled red.

The intake attaches to front end as shown in my original pic and push fits in the area circled green.

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With the cobalt pipe, presumably, it’s a nose cone off job? Is that quite a p.i.a? I worry about all those little clips & things.

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I had already removed front bumper to carry out splitter install and treat any steel areas for rust.

I think it would need removing for the intake pipe as you need to gain access to remove original intake pipework.

It’s a simple process, few bolts here and there and the plastic clips you mentioned, the push in the centre type to release.

If you break any there readily available online for pennies.

Cobalt install is a doddle, one bolt and a bit of thread lock.

Edit: As you can see the mouth of intake sits quite high up behind grille

I’ve an NC1, the reg plate covered maybe half of intake mouth.

I decided to do away with reg plate holder in favour of a smaller plate that will attach directly to bumper.

I also drilled out the honeycomb blanks that are standard on the original grille (upper half of grille) to allow a more unrestricted flow into intake.

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Thanks for the info, that is really helpful knowledge :ok_hand:

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Not true Ian.

No difference to sound, but I had a Skuzzle fitted and it allowed Autotronix Developments to add 7bhp to the map

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I think that was the only one that had any verified impact, however no longer in active production though possibly available used or from held stock.

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Still available as the Ramair kit…Mx-5 parts sell it

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Direct also Performance Foam Induction Kit for 1.8i & 2.0i Mazda MX5 NC - Automotive Air Filters | Ramair Filters I run one on my sprint car

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but you need to map it, thats the important bit

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They saw you coming, sorry

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