B8/8.5 S4 Factory Airbox Modification

[jackbert]

this project started out with me being not content with the current intake offerings

after 8 months of research and development, i finally completed my vision, a hybrid box between open and closed element while maintaining a factory look.

i started by added a scoop to the front grill to direct cold air into the factory air box, then i opened up the factory foglight grill, ported the factory air box and ran ducting to the foglight grill to direct more cold air into the factory air box, then i added a titanium intake tube and a itg foam intake filter and finally i drilled holes on top of the factory intake lid to amplify the supercharger whine.

in theory this setup should have lower iat but i have no data to back this theory up, i would like to log some data with the factory set up and compare to see if my theory is true. i did gain 5awhp with this set up on a hot dyno day.

what do you think? could this intake box pass for as factory?

[GoneQuantum]

Awesome work. Definitely could pass for stock. Was there a noticeable increase in supercharger whine?

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[jackbert]

Awesome work. Definitely could pass for stock. Was there a noticeable increase in supercharger whine?

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Thank you!

There is a YouTube link at the very end of the photos, yes night and day but it’s not as loud as an open element intake.

[GoneQuantum]

Thank you!

There is a YouTube link at the very end of the photos, yes night and day but it’s not as loud as an open element intake.

Just saw that, sounds good! Not too loud at all.

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[CinCrz]

I like your idea for the template for putting the holes in the lid. Good thinking.


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[jackbert]

I like your idea for the template for putting the holes in the lid. Good thinking.


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Thank you, I wanted to keep it consistent. I’m planning on making a few of these if anyone is interested. Send me a PM, we can work something out.

[CinCrz]

Thank you, I wanted to keep it consistent. I’m planning on making a few of these if anyone is interested. Send me a PM, we can work something out.

I’d be interested in just the file I could use to print that template off. I already have a modified stock air box but I’ve been contemplating adding some holes to the lid like you did to increase the audible supercharger whine.


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[Cacevedo]

I’d be interested in just the file I could use to print that template off. I already have a modified stock air box but I’ve been contemplating adding some holes to the lid like you did to increase the audible supercharger whine.


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+1

[cadguy77]

Where did you get the titanium tube from?

[Audi_Jer]

Any concern about sucking up water during rain/wet road driving? That's the only concern I'd have having an air intake that low to the ground.

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[LoloHaole]

That could easily pass for stock! I like that scoop, too.

The 034 silicone tube is pretty stock looking, but mine is an awkward fit. I'd love to try that Ti tube to see if a "hard pipe" amplifies the SC whine at all. Where did you get it?

I took a hackish approach and just cut off the bottom half of my airbox so my air filter is exposed, which gave me more audible whine, but I still want more SC volume.

[killer_s4]

Does that titanium absorb a lot of engine bay heat?

[Clintster]

Looks great! I love way you did the holes in the top cover of the airbox, very stock looking. Question though, and maybe this is obvious to some, but your dyno shows an increase in horsepower but an even larger decrease in torque. What's that about?

Edit: typo

[oaybar007]

Very clean work!

[jackbert]

Where did you get the titanium tube from?

it was custom made by a performance shop

Just saw that, sounds good! Not too loud at all.

Sent from my HD1905 using Tapatalk

I’m content with the amount of whine it produces, it’s not over bearing. I have a few friends with open elements and after a while it gets old.

I’d be interested in just the file I could use to print that template off. I already have a modified stock air box but I’ve been contemplating adding some holes to the lid like you did to increase the audible supercharger whine.


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I went through a lot of r&d and wasted a few lids while making these holes look as factory as possible, with that being said I am not sharing the template but I would be happy to make one for you, I just need a core.

Any concern about sucking up water during rain/wet road driving? That's the only concern I'd have having an air intake that low to the ground.

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That is a concern after seeing people hydrolock their 3.0t. I plan on addressing this issue by blocking off or disconnecting the fog light air duct from the box. I have a spare foglight grill with no holes that I could swap out block the air duct even more. if I drove over a deep puddle, it would be game over.

That could easily pass for stock! I like that scoop, too.

The 034 silicone tube is pretty stock looking, but mine is an awkward fit. I'd love to try that Ti tube to see if a "hard pipe" amplifies the SC whine at all. Where did you get it?

I took a hackish approach and just cut off the bottom half of my airbox so my air filter is exposed, which gave me more audible whine, but I still want more SC volume.

Thank you. Honestly, there minimal benefits of having a titanium intake tube, it just under the hood bling. I the sound from a metal and silicone tube is negligible. I tried an AWE silicone tube and did not notice any audible difference. The factory box really muffles the sc whine, the more it you cut off the louder your sc whine will be. The tube was custom made by a performance shop.

Does that titanium absorb a lot of engine bay heat?

Yes, everything under the hood will be expose to all the engine heat. There isn’t any way around it but it feed to intake filter cold air.

Looks great! I love way you did the holes in the top cover of the airbox, very stock looking. Question though, and maybe this is obvious to some, but your dyno shows an increase in horsepower but an even larger decrease in torque. What's that about?

Edit: typo

Thank you! That was my goal.

That’s a great question. I have a few theories. I might be wrong with these theory but if anyone knows please chime in

1. I swapped to a bigger diameter wheel for the second dyno. First dyno graph was with 255/35 19x8.5 +43 peelers (54lbs), second dyno graph is with 265/35 19x9.5 +35 bbs (50lbs)
2. Bigger intake tube = more air and less velocity; velocity = torque
3. Not tuned for more air

Very clean work!

Thank you!

[cadguy77]

it was custom made by a performance shop



I’m content with the amount of whine it produces, it’s not over bearing. I have a few friends with open elements and after a while it gets old.



I went through a lot of r&d and wasted a few lids while making these holes look as factory as possible, with that being said I am not sharing the template but I would be happy to make one for you, I just need a core.



That is a concern after seeing people hydrolock their 3.0t. I plan on addressing this issue by blocking off or disconnecting the fog light air duct from the box. I have a spare foglight grill with no holes that I could swap out block the air duct even more. if I drove over a deep puddle, it would be game over.



Thank you. Honestly, there minimal benefits of having a titanium intake tube, it just under the hood bling. I the sound from a metal and silicone tube is negligible. I tried an AWE silicone tube and did not notice any audible difference. The factory box really muffles the sc whine, the more it you cut off the louder your sc whine will be. The tube was custom made by a performance shop.



Yes, everything under the hood will be expose to all the engine heat. There isn’t any way around it but it feed to intake filter cold air.



Thank you! That was my goal.

That’s a great question. I have a few theories. I might be wrong with these theory but if anyone knows please chime in

1. I swapped to a bigger diameter wheel for the second dyno. First dyno graph was with 255/35 19x8.5 +43 peelers (54lbs), second dyno graph is with 265/35 19x9.5 +35 bbs (50lbs)
2. Bigger intake tube = more air and less velocity; velocity = torque
3. Not tuned for more air



Thank you!

Only reason I asked is the intake tube looks very similar to this offering

https://garageautosports.com/collect...31930258358368

[doughboy17]

Such a clean look. Fantastic job! I speculate drilling the holes on the top of the box does increase IAT's, though.