I am looking to make a DIY cold air intake system for my nb. My goal is to simply make the intake slightly louder, but I do not want to sacrifice the performance of the intake. I do not want to have an intake that is taking in hot air. Can anyone recommend or explain a simple cold air intake system without sacrificing the MAF sensor also. Thanks guys.
JimmyNb
NB DIY Cold Air Intake System
Moderators: timk, Stu, -alex, miata, StanTheMan, greenMachine, ManiacLachy, Daffy, zombie, Andrew, The American, Lokiel
- Jimmynb
- Driver
- Posts: 82
- Joined: Thu Feb 26, 2015 10:29 pm
- Vehicle: NB8A
- hks_kansei
- Speed Racer
- Posts: 6154
- Joined: Tue Feb 03, 2009 10:43 am
- Vehicle: NB8A
- Location: Victoria
Re: NB DIY Cold Air Intake System
Simplest and cheapest is to buy a pod filter and stick it onto the AFM. (remove airbox)
Total cost about $30
Performance wise, bugger all difference to stock, it will be taking in hot air though.
Next option is the same, but with heat shielding around the pod.
Measure and cut metal sheets to fully enclose the filter from engine bay air, ducting to either inside the guard or behind headlight.
Cost $30 pod plus maybe $50 metal
Another option is a short intake (coldside) buy a silcone elbow, some clamps, and a pod filter.
remove airbox, crosspipe. unwrap the loom for the AFM wires and pull AFM wires free until enouhg to reach throttle body side. re-wrap loom.
attach AFM joiner and pod behidn passenger headlight, find a new home for the temp sensor (mine's under the rad support)
if you want you can shield from engine bay heat and enclose the lot.
Cost about $30 pod, $40 joiner, $10 clamps
Last and easiest option for just noise is to cut holes in the dirty side of the airbox, or hack out the snorkel opening and attach a larger snorkel.
Cost is nothing, performance gain nothing, just some noise.
Total cost about $30
Performance wise, bugger all difference to stock, it will be taking in hot air though.
Next option is the same, but with heat shielding around the pod.
Measure and cut metal sheets to fully enclose the filter from engine bay air, ducting to either inside the guard or behind headlight.
Cost $30 pod plus maybe $50 metal
Another option is a short intake (coldside) buy a silcone elbow, some clamps, and a pod filter.
remove airbox, crosspipe. unwrap the loom for the AFM wires and pull AFM wires free until enouhg to reach throttle body side. re-wrap loom.
attach AFM joiner and pod behidn passenger headlight, find a new home for the temp sensor (mine's under the rad support)
if you want you can shield from engine bay heat and enclose the lot.
Cost about $30 pod, $40 joiner, $10 clamps
Last and easiest option for just noise is to cut holes in the dirty side of the airbox, or hack out the snorkel opening and attach a larger snorkel.
Cost is nothing, performance gain nothing, just some noise.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)
- hks_kansei
- Speed Racer
- Posts: 6154
- Joined: Tue Feb 03, 2009 10:43 am
- Vehicle: NB8A
- Location: Victoria
Re: NB DIY Cold Air Intake System
I'll also add, that my car has had the following fitted at some stage.
OEM airbox
Mania style intake
Bare pod on AFM
Coldside intake
Of them all, the mania was loudest inside the car, the Coldside loudest outside.
The mania constantly filled with leaves and was a prick to clean.
Power wise, unless you're also tuning the car to suit them you'll get stuff all difference.
I currently have the coldside on the car simply because I like the sound it makes, power wise it does nothing.
11084187_10206728058268972_3698057527085522336_o by hks_kansei, on Flickr
OEM airbox
Mania style intake
Bare pod on AFM
Coldside intake
Of them all, the mania was loudest inside the car, the Coldside loudest outside.
The mania constantly filled with leaves and was a prick to clean.
Power wise, unless you're also tuning the car to suit them you'll get stuff all difference.
I currently have the coldside on the car simply because I like the sound it makes, power wise it does nothing.

1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)
- smy0003
- Racing Driver
- Posts: 1870
- Joined: Mon Dec 30, 2013 12:35 pm
- Vehicle: NA8
- Location: Melbourne
Re: NB DIY Cold Air Intake System
I did this:

If you want loud, this is it.

If you want loud, this is it.
[b]Then: Sunlight Silver NB8B
Now: Chaste White NA8
Now: Chaste White NA8
- Jimmynb
- Driver
- Posts: 82
- Joined: Thu Feb 26, 2015 10:29 pm
- Vehicle: NB8A
Re: NB DIY Cold Air Intake System
HKS: How is the coldside intake getting sufficient air flow to it? Did you custom make a snorkel? Or is it enough without it?
SMY: Surely that is now a hot air intake as it is positioned right next to the exhaust and engine heat?
SMY: Surely that is now a hot air intake as it is positioned right next to the exhaust and engine heat?
- hks_kansei
- Speed Racer
- Posts: 6154
- Joined: Tue Feb 03, 2009 10:43 am
- Vehicle: NB8A
- Location: Victoria
Re: NB DIY Cold Air Intake System
Jimmynb wrote:HKS: How is the coldside intake getting sufficient air flow to it? Did you custom make a snorkel? Or is it enough without it?
It gets sufficient airflow because the bonnet etc are not airtight.
As for cool air flow, currently it relies upon the gap between the headlight and bonnet, and whatever cool air bleeds past the radiator. For the most part though it's just sucking ambient engine bay air.
One day when I can be bothered i'll be boxing it up and ducting air from the front, most likely i'll have a bellmouth down in the grille area and feed the duct up through the gap to the side of the radiator.
For now though (and let's face it, i'm lazy so probably forever) it's an intake for sound only, the air on that side of the bay will be only marginally cooler (if at all)
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)
- smy0003
- Racing Driver
- Posts: 1870
- Joined: Mon Dec 30, 2013 12:35 pm
- Vehicle: NA8
- Location: Melbourne
Re: NB DIY Cold Air Intake System
Sure is a hot air intake.
My IAT hovers around 60 degrees most days.
Sent from my LG-H815 using Tapatalk
My IAT hovers around 60 degrees most days.
Sent from my LG-H815 using Tapatalk
[b]Then: Sunlight Silver NB8B
Now: Chaste White NA8
Now: Chaste White NA8
-
- Speed Racer
- Posts: 12012
- Joined: Mon Aug 08, 2005 11:35 pm
- Vehicle: Clubman
- Location: Melbourne
Re: NB DIY Cold Air Intake System
Stewart Mk1, Stewart Mk2/Mania style DIY & DDM style DIY:
viewtopic.php?f=57&t=68094
viewtopic.php?f=57&t=68094
Return to “MX5 Engines, Transmission & Final Drive”
Who is online
Users browsing this forum: No registered users and 5 guests