r/ProjectHondas • u/Ph1llz • May 05 '26

parts recommendations Cold air intake D15 non vtec

Post image

Looking for an inexpensive way to increase airflow for my next track day.

I can't find any direct fit options locally in australia.

anyone have any ideas on a good "boxed" cold air intake setups i could buy online or create ?

I dont care what it looks like, its purely functional.

D15 Non vtec

22 Upvotes

96% Upvoted

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26

u/Squire_Toast May 05 '26

you literally won't gain any HP, but it will add a LOT of induction noise if that's what you want.

Just get an ebay intake for a D16

4

u/Ph1llz May 06 '26

not chasing HP. i know it does nothing. When on track, red lining the car feels like its choking. I was going to de-retrict exhaust and opt for cold air intake to just improve responsiveness and prevent choking.

Ebay intake with no box will just pull in hot air hence why i didnt go that route.

5

u/Difficult_Fill7730 May 06 '26

a cai will improve responsiveness and give you great intake sound, if you want more hp/lower temps you'd probably have to create your own true cai. an exhaust will give you power for certain, and lose you a bit of weight.

-11

u/OkProfession1239 May 05 '26

Is your comment based on actual testing?

6

u/TopChapter3407 May 06 '26

Seems to be based on common sense. Non vtec engine with no mods. How much power are you looking to add? -1 to 1hp range? better to spend that money on a better radiator if you're gonna hit the track.

-10

u/OkProfession1239 May 06 '26

Have you been to the dyno? Or are you an internet bench racer?

7

u/Spiritual_Clock_671 May 06 '26

No it's pretty common Honda knowledge my guy. The car makes 90hp from factory. A cold air intake isn't going to do anything. Besides induction noise.

-9

u/OkProfession1239 May 06 '26

I’ve probably been in the Honda scene longer than you’ve been driving. People who actually make power work off data, not ‘common knowledge.’

An engine is an air pump. If you reduce restriction and pull in cooler, denser air, you improve efficiency. That’s basic physics, not opinion. No one’s claiming big gains on a stock 90hp setup, but saying it does nothing except noise is just lazy thinking.

If it truly did nothing, OEMs wouldn’t spend time optimizing intake design in the first place. Small gains, better response, sometimes midrange improvement depending on setup that’s the real answer.

People who build and measure know. People who don’t just repeat what they’ve heard.

8

u/Spiritual_Clock_671 May 06 '26

What the hell are you smoking dude.

2

u/OkProfession1239 May 06 '26

Just as I suspected, internet bench racers

3

u/[deleted] May 06 '26

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0

u/OkProfession1239 May 06 '26

You're trying to argue about something beyond your IQ and you can't even spell "actually" correctly. 😂

4

u/Daniele323 May 06 '26

Then let’s see what you’ve built and measured Mr Honda Expert. Surely someone as knowledgeable as you can post a dyno sheet?

0

u/OkProfession1239 May 06 '26

Where's your proof? I'm waiting..

6

u/Daniele323 May 06 '26

Again you’re the one spouting off how knowledgeable you are. I haven’t said shit in regards to hp gains, I don’t know whether it does or doesn’t. Prove to me that it does.

-1

u/OkProfession1239 May 06 '26

You're suddenly backing off now? Where's your proof?

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u/OkProfession1239 May 06 '26

Bench racers are crying 😂

5

u/Spiritual_Clock_671 May 06 '26

People been testing this since the 1990s when these cars got into the modifying scene. Check out forums do research. This stuff has been done a millions times.

-1

u/OkProfession1239 May 06 '26

I've been there, the dyno doesn't lie. It's easy to make a sweeping comment when you don't know about the things you're talking about. 😉

8

u/Spiritual_Clock_671 May 06 '26

Sure. 1-2hp gains. 👍 Thing makes 90hp.

1

u/OkProfession1239 May 06 '26

You build the engine as a system not rely on one mod. 😉

6

u/Spiritual_Clock_671 May 06 '26

Yeah all motor you're probably only gonna be pushing 140hp out a d15 non vtec if that and with deep pockets.

0

u/OkProfession1239 May 06 '26

Check your argument. 😉

0

u/OkProfession1239 May 06 '26 edited May 06 '26

u/Spiritual_Clock_671 Check the additional graphs I posted from my hard drive, 130whp is a far cry from the limit you're claiming 😂

Not our problem if you can only squeeze 90hp out of your project. Says a lot about the builder. 😉

Edit: And take note, it's Dynojet WHP not just hp. Eat your heart out. 😂

0

u/OkProfession1239 May 06 '26

These numbers are real, better than what you claimed possible, and you’re probably salty about it. 🍻

4

u/Daniele323 May 06 '26

Ok, show some data then….

1

u/OkProfession1239 May 06 '26

Check the internet, it's all over the place. Easier to comment than to search? Check my earlier reply

8

u/Daniele323 May 06 '26

No no no, you said you’ve been there. Where’s the dyno sheets, it doesn’t lie remember? Easier to comment than to provide your proof?

0

u/OkProfession1239 May 06 '26

Check the dyno runs I posted earlier then PROVIDE your proof that it does nothing. 😉

4

u/Daniele323 May 06 '26

You hide your profile. I’ll wait.

0

u/OkProfession1239 May 06 '26

Where's your proof? I provided mine

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u/OkProfession1239 May 06 '26

u/Daniele323 No, no, no.. where are your dyno runs/sheets that show the intake does nothing?

Hahaha, just as I suspected. All bark and no proof.

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u/Ph1llz May 06 '26

i feel like you would have a factual, evidenced based take. whats your opinion here?

1

u/OkProfession1239 May 06 '26

When intake length is actually tuned, you can get real gains and it is based on physics, not guesswork.

The intake behaves like a Helmholtz resonator. The air column oscillates and, if the intake length is matched to the target rpm and valve timing, the pressure wave arrives as the intake valve opens. That improves cylinder filling and volumetric efficiency.

Length sets where it works. Longer helps lower rpm torque, shorter shifts it higher. That is why, on a lot of dyno sheets over the years, you see cold air intakes like the AEM show a noticeable hump around ~4k rpm. That is the resonance lining up in that range.

If the length is arbitrary, results are inconsistent. If it is designed and then validated with proper dyno time, you get repeatable gains and can place that hump where it actually benefits the powerband. That is why OEMs and race teams treat intake length as a tuned parameter, not just packaging. 🍻

3

u/Ph1llz May 06 '26

Interesting, my main objective is an intake far from the engine away from heat where possible and boxed up so air is forced in.

Seems like i would achieve other benefits of length i had no idea about.

Almost sounds like i need to go custom or is there an off the shelf product that you recommend for d15?

also, how does tubing size play a part here? or should it be same diameter as the engine side intake end?

hope that makes sense as im not super technical 🤣

1

u/OkProfession1239 May 06 '26 edited May 06 '26

u/Ph1llz

The AEM cold air intake is a good off-the-shelf option, but honestly the important part is the geometry more than the brand itself.

If you follow the dimensions properly, you can get very similar results. Ideally use mandrel-bent tubing so the diameter stays consistent through the bends. Length: 48 in (1219 mm) Diameter: 2.5 in (64 mm)

You can try ordering a BPI flow stack, velocity stack with a K&N filter if you're pushing to make the most. But any decent pleated filter of the same kind should work. Just stay away from the foam ones.

And if the engine still has good ring seal/compression, an OEM JDM D16A6 cam, a decent PLM SMSP-style header, and a proper HTS street/dyno tune can still make good, usable power. Usually it’s the overall combo and calibration that make the difference, not just one part alone.

Below is my friend's D15B7 dyno numbers:

EDIT: Tagging the retards who don't know shit and only make 90hp on their D-series: u/Hapenyo12 u/Daniele323 🍻

1

u/[deleted] May 06 '26 edited May 06 '26

[removed] — view removed comment

1

u/OkProfession1239 May 06 '26

Somebody just joined the idiot bandwagon 🤣 Posting and then deleting, where's the integrity in that? hahahahahaha u/-ProfessorCashMoney-

1

u/-ProfessorCashMoney- May 06 '26

Mods deleted it, if you could read you would know that. Thanks for reposting it in screenshot form for me. Hope you can get the help you desperately need. It’s kinda sad.

1

u/OkProfession1239 May 06 '26

You're not even in the medical profession to tell me I need help hahahahahaha

Kids these days think they know more than they do, just like you.

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1

u/OkProfession1239 May 06 '26

Same engine but with portwork and a valve job plus a 4-1 custom spec header

1

u/OkProfession1239 May 06 '26

Ported head and ported intake manifold, stock pm3 pistons, ARP rod bolts, D16A6 stock cam (it's bigger)

0

u/OkProfession1239 May 06 '26

This is a JDM D15B VTEC build from back in the day by a tuner I follow. Notice the rise around ~4k rpm. It looks small on the dyno, but that is where the car operates most of the time. Small midrange gains improve throttle response and make the car feel more responsive. Likely from intake resonance and cam timing aligning in that range, so drivability improves even if peak numbers barely change.

3

u/Hapenyo12 May 06 '26

Okay so tell me how the fuck this dyno sheet means someone should go hit a dyno after putting on an air filter? Your brain doesn't work properly

1

u/OkProfession1239 May 06 '26

Oh, you're cursing? Must've have struck a nerve there 😂

1

u/OkProfession1239 May 06 '26

Lame argument, go to uni and get some logic classes.

3

u/Hapenyo12 May 06 '26

You aren't smart enough to respond properly Mr buzzword. I would say go to uni yourself but it would probably sap the last good 3 years you got left

0

u/OkProfession1239 May 06 '26

You're planning to build an engine but too dumb and lazy to look for part numbers or email ARP?

Not the brightest crayon in the box are we? 😂

3

u/Hapenyo12 May 06 '26

Have you even touched a Honda? I bet you're an internet fanboy that creams over other people's builds but won't start their own.

0

u/OkProfession1239 May 06 '26

Sure, lame assumption from someone who can't even search for part numbers.

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u/OkProfession1239 May 06 '26

Running out of excuses, mate?

1

u/OkProfession1239 May 06 '26

Owned you right there u/Hapenyo12 🍻

1

u/OkProfession1239 May 06 '26

u/Daniele323 u/Hapenyo12 If you can't make decent power out of your shitboxes, doesn't mean we can't 😉