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DIY Intake. So far feels promising...

2811 Views 37 Replies 10 Participants Last post by  Article_Automotives
I've hated the stock intake every since I saw it. It just has to be restrictive and with miles of plastic duct, that kinks, morphs in different shapes and sucks from a small opening above the radiator, it cant be good, esp if you're gonna try to push past stock hp levels. When I built my intake for my Audi, I never really felt a difference when I was piecing it together. It was fast that's for sure but I never noticed what a difference it made until I traded it in. I put in the stock intake and it felt super super laggy and slow. Crazy

So when I started throwing codes from the Jb4 and probably my failing Diverter valves (turbo performance codes), I kept thinking the stock intake is probably hurting. Most of the times when it threw those codes, it took forever for it build boost. I built a cheap intake for my Audi how hard could it be for the quad? Well this may look simple but trust me it took a bit of time to figure out what would fit where and where would be the best place to keep the heat out, etc...

But this is what I came up with. Two 3", 90 deg, Aluminum tube (Bought from Amazon), a 2 K&N filters, some hose clamps (These tool-less ones are the best) and some sheet foam.

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Ok, so gets down with it. Yes, it feels much faster and dang, the lag has been cut in half. I've been driving it all after noon (Getting JB4 logs and taking the family to dinner, watching the IATs, etc). And just once it felt soft but the other times, I was feeling quite impressed. Before, I felt the longer I drive the quad the slower it feels. I'll try to get draggy runs next weekend and I'm thinking there will be something to show... stay tuned.

The notes: The big one, its louder but just a bit. Kinda disappointing. Driving normally, you might not notice. A bit more faint whistle at low rpms but no wooshes, blow off valve farts, just.. well, all I hear is my wonderful Ragazzon exhaust once it goes.

IATs seem a bit warmer when on it. I'm seeing around 5 degs above ambient. During stop and go traffic, it gets to about 10 - 20 degs over which is what I saw with stock but it can't be as good as stock at keeping the heat out. When I came home from driving, I felt the intake and it was ice cold and the engine bay was hot.. so if you're moving its not too bad?

I don't think I can get the stock clamps back on the turbo inlets. I've been taking the stock air box in and out since I got the quad and those clamps are easy peasy. But those lower ones.. dang.

I found oil in my drivers side turbo inlet. No biggie, you can see the EGR and PCV right there but my passenger side was dry as a bone.. =(

Here's the one that stumps me. I capped the high pressure venturi a few months ago. Figured its just a boost leak (I felt no difference). No codes. Then when I just left the carbon canister hose just hanging in the engine bay when I did my first test drive, no cel again. Wow. So i just left it disconnected for now but I may put a rubber tube back to my inake for it.

So hoping for the best and your results may vary (my car is mildly tuned. Discuss...

(and if anyone copies my intake, we all know who think he did it first!!)
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I've been thinking of doing this ever since I removed the intake I made last year, I'm getting to it later this month since temps are more palatable in Chicago. My biggest concern has been those venturi valves, do you have any pictures of your current "solution"? Thanks,

I'm happy to see someone else thought the same thing I had in mind!
So, why not keep the first part of the air ducts (marked in red)? Those would help you direct air directly into the filters...and place the filters ("marked" in blue") in front of them??
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Thanks for the answer. I guess I'll be able to assess the situation when I attempt this. You got me all excited to get it done. I'm out of town this week still, I might have to jump into this next week! :)
Thanks for the detailed accounts. It could be that your FYI air intake is still soaking a lot of heat from the rest of the engine at take off speeds (0 - ~25-30 MPH) and it hurts the take off. I remember my home made air intake was hurting 3 tenths in the quarter mile consistently (although it felt it pulled harder at higher speeds)...perhaps something similar is happening with your system. I guess you could try to isolate those air filters better from the rest of the engine.
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