DIY Intake

Cbtech

So at first when i thought of this idea I was excited to try a DIY intake but couldnt seem to find a real good way to do it without a Frankenstein coupler nightmare. I currently have the K&N typhoon pop chargers which, as you can see below has the maf tub and then the filters attached to a heat shield. I was thinking i could use the exsiting tube as my starting point and run something past the firewall but i didnt know what....



so a few weeks ago I was walking through a local performance superstore here in Sacramento (Tognotties) and saw some exhaust flex pipe ($21.95 for 6 feet). it was 2.5 internal diameter and fairly smooth even when bent.



So that got me thinking...I can use my existing MAF tube, couple on the flex tube, and run the pipe Stillen style since it was flexible. My buddy Dave (FYD) was laughing at me because he thought that it was another "dryer hose" mock up idea that I had but I thought that this could really work!

so here's what we needed:

• K&N Typhoon or any other MAF tube that is compatible
• 6 Feet of 2.5" exhaust Flex Pipe
• 2.75 - 2.75 silicone couplers
• K&N cone filter or similar (smaller tube filter works too)
• High Heat Spray paint
• **Optional heat reflective Tape

First take your bumper off and remove all necessary airboxes etc you need to cut out your firewall hole just the same as you would with the stillen G3 install. We marked our spot based on the diameter of the flex tube:



We used a dremmel to widen the hole and test fitted our piping to make sure that it would make it through.



After making our test fit we cut the pipe down to 2' 6" on the right and 2' 8" on the left (measure again to make sure)

once we made our cuts we put the filters on the ends and clamped them down. This tubing is very durable and wont crush easily. We pressed the filters with the pipe connected to where we wanted and installed the upper bracket. The filters that came with the Typhoon set up fit perfectly and were actually held in by the upper bracket quite nicely.





We took everything apart and moved onto the next step.

***FIRST OFF*** you must cover your AC lines to prevent them from being damaged by the tubing rubbing against them.

I used some fuel line hose and zip tied them on the lines to prevent this:



Next since the flex tube is not galvanized it can rust. the way that you can prevent that is by spraying it with a high heat Rustoleum spray paint.





The way you cover the interior of the flex pipe is by "fogging" the inside. You hold the can of paint about 6 inches from the opening and spray directly into it. I did 2 coats to make sure everything was covered.



After the paint dried i wrapped the pipe that was exposed to the engine compartment with a heat reflective fiberglass tape i got on Amazon for $15. it stuck well and had no issues with covering 1/3rd of the pipe.

After the wrapping was done I put everything back together the same as the original mock up with the 2.75 - 2.75 coupler and tightened it all down.

Final product:







All in all the whole DIY cost me around $50 and there is a noticeable difference in performance. Before doing this my average temps were around 20-25 above ambient temperatures based on freeway driving.




With this new piping the average freeway temps are between 5-6 Degrees above ambient temperature. to me this is well worth the additional $50. For some, they may argue, "well why not just spend the extra $100-$200 and get a G3?" For me, a nice well done DIY that saves me that $100-$200 and does the exact same job as the higher priced competitors is more of a feeling of satisfaction.

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Read T

Not worried about the rattlecan flaking off eventually and potentially hurting the vroom-vroom or sensors? I say this when one of my cars has no filter or room for air filter at all.

Interesting to see how this compares in temperatures and laminar flow to other intakes. It seems ducting in cooler air using flexpipes to the shorter intakes might have the best of both worlds, but Kudos for a DIY.

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thangcu35

Not bad. I'm sure it will perform better than oem but those ripples in the tubes are not going to help with flow. What i did with my typhoon intake was flipped it around and run 3" piping to the front.

ANMVQ

I thought about this but stayed away because the inside on the tubes are not smooth, Turbulence = :/.. I how ever keep the stock air boxes and added a air intake mount plate to each one of the rad support ram air ducts, used silicone elbows and air ducts at the ends to make my own cold air intake. See my mod stock air box thread.

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SouthArk370Z

Great idea and excellent execution, even if the extra turbulence turns out to rob a little power. Rep'd.

It would be interesting to see some data on whether or not the cooler air offsets the added turbulence.

It might be worthwhile to get someone to bend some tubing for you. A good custom muffler shop should be able to do it.

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Cbtech

Thank you sir! I did look into some muffler shops locally to see about doing some pipe bending for me but most shops around town did not do mandrel bending. And in order to get the tubing that I wanted, done it would have been cost prohibitive unless I had a large lot of pipes to bend. From what I understand a little bit of turbulence isn't bad, but I could be wrong. But the interior of these pipes are quite smooth with only a few ridges to create the turbulence. They're not like large dryer vent hose that is quite ridged and can definitely cause a lot of turbulence.

Another issue that I didn't bring up was with having the typhoon sitting in the engine bay; while at a stoplight, the maf temperatures would increase anywhere between 30 to 50 degrees hotter in the summer time while waiting for the light to change. Which would in turn cause the motor to bog down when launching off the line.

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SuperDave

True, I thought I had shared my story with Ruben about the dryer hose intake on my Honda Civic 12 years ago in hopes to prevent him from doing it, not to encourage it.

However, these supplies impressed even me. The flex pipe is very smooth on the inside and difficult to bend (had to wrap around my knee and pull with both hands). The filters attach to the piping very securely. This particular pipe was very rigid and not as bumpy on the inside as you might expect.


Hi temp engine enamel, no, this is not a concern. It's main purpose was to prevent rust, as this was bare metal.

True, there is some turbulence caused by the non-smooth inside of the pipe, however not as much as you would think. Additionally, some turbulence in the intake is a good thing. I was genuinely impressed and excited by the pipe Ruben had found. I'm sure the benefits outweigh the cons with this particular piping.

Overall if we were to do another, I might bump it up to 3" piping which would get reduced to 2.75" at the MAF and K&N tubing, which would definitely factor out any turbulence due to the flex pipe.

Pics and "most of the work" credit goes to me, FYR. Just kidding, I don't want my name associated anywhere near this thing

Also, good work with the write up Ruben, nice detail and pics.

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LAVA

you can always buy cheap mandrel bent tubing here

Nice job!

SuperDave

We thought about piecing together pre-bent pipes or even maf tubes, as you can get those in different sizes with different bends as well. Only problem was we didn't know the exact path and dimensions we needed. We do now, and when we do my car, that's what I'll use! FYR

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Cbtech

do you have any more pix of the coupler and pipe going through the firewall?

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Cbtech

yeah but the Jew will end up spending a lot more for his set up than me :P

FYD give me my heat shields back bish!!

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Cbtech

thank you... and Nice find...i didnt think about looking up mandrel bent piping on ebay. My only concern was it not being specifically bent for this application or fitment issues.

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SilverValk01

How long is each pipe?
Nvm I over looked it lol

synolimit

DIY cai?

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Cbtech

Well done Scott! i might have you beat on cost though :P

Had i seen your DIY i probably would have done what you did

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