Turbo Cold Air Intake Questions

[Cool Mr Steve]

I would like to see pictures and hear details on how everyone with a cold air intake set up their system. By the way, I am interested in running the CAI without a MAFT, so I want to see setups with the MAF in place. Thanks in advance!

 

[BGGSTin]

If you just mean how the intake pipe is led to the turbo I can post up some pics later.
A cold air intake on a turbo car is pointless though, In an N/A car it helps because it's getting cooler air than in the engine bay that will only go through piping to the intake, so it will still be cooler than the ambient temp. under the hood.
A forced induction car however has no use for it, supercharged or turbo, the compression of the air alone heats the air up which would make cold air induction pointless combined with the fact that the turbine housing will heat the air as well. We get the cold air effect from intercoolers.

But if you did mean just how we have the intake to the turbo, I'll resize some pics and try to putem' up

 

[eclipsh]

Don't you just love how EVERY time a cold air intake is brought up in regards to a turbo car someone says you shouldn't do it, it doesn't do any good, blah blah blah... Yet data logs constantly show reduced knock and increased timing from doing it.

Sorry, I could help if you had a 1GA, I just thought it was funny that history keeps repeating itself.

This guy has an Injen CAI on his 2G.

Apexi for this one.

How about one with pictures.

So anyhow, I just did a site members search for CAI. I'd go directly ask someone who's done it. Hope this helps.

 

[napkinthief]

Achieving the CAI for a turbo is actually very simple, just takes a little bit of planning and a good big piece of thick cardboard or plastic. Many people use those "vote for me" lawn signs because they are stiff strong and simply...they work. All you need to do is block off the intake from the engine bay area, using either a small pipe to extend the filter out to the left on a 4g63, then block off the area with the sign and get it to stay in place. If you check out the tech articles, there are 2 or 3 guides.

 

[FORMONTOYA]

Don't you just love how EVERY time a cold air intake is brought up in regards to a turbo car someone says you shouldn't do it, it doesn't do any good, blah blah blah... Yet data logs constantly show reduced knock and increased timing from doing it.

none of these fit the description of a "cold air intake" which means the filter element is not inside the engine compartment and you will not find one for the turbo because it would probably suck water up into the turbo. the best that you find is if someone installs a shield or "box" around the cone filter to decrease temps at the filter. what gets passed of as a "cold air intake" really surprises me.


jim

 

[TJGoSurf]

About the only way I could think to do it would be if you had a FMIC, and you mounted the filter where the SMIC used to be and rework your FMIC piping. Anywhere else and you're getting a really long pipe with lots of connections that could leak. But then you have the issue of rain coming in, I know they make a bypass valve for CAI, but I have no idea how it works.

I would just build the box.

 

[wret]

Actually, the dimensions of my setup are based on the Injen intake with stock MAS. The black piece you see between the intake and the air box was fabricated to be about the same dimensions as the MAS.

And TJGoSurf is correct. Unless you have an FMIC and you route the piping so it doesn't pass through the hole under the stock air box. This kind of setup won't do you much good.

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[tstkl]

that kinda looks like your starving your turbo for air....

i saw someone on this site had a similar set up, except he had a radiator pipe with a funel at the end that he attached to his heat sheild, and pointed the funel towards the front of his car, so he had a somewhat ram air/cold air intake set up.... the funel would lead air to the filter which was in an air box like the one shown..... he said throttle response was much better...

 

[wret]

You mean kind of like this?

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[eclipsh]

So Wret, I read a thread I can't find anymore where a guy did that setup with aluminum ducting and his temps actually dropped below ambient from the aluminum cooling the air as it went by. I don't know how true it was but it could be a fun thing to try out instead of the plastic it looks like you're using. Just for the sake of science of course

 

[tstkl]

no that wasnt it, but its very similar, i saw it on a 1g, but thats the same idea



http://dsmtuners.com/forums/showthread.php?t=195667&highlight=11*

 

[wret]

So Wret, I read a thread I can't find anymore where a guy did that setup with aluminum ducting and his temps actually dropped below ambient from the aluminum cooling the air as it went by. I don't know how true it was but it could be a fun thing to try out instead of the plastic it looks like you're using. Just for the sake of science of course

Well for one thing, the material doesn't matter much as far as heat transfer through conduction is concerned. There simply is not enough surface area in the duct or dwell time. As a matter of fact, you will find that the duct itself is almost exactly the same temperature as the air running though it rather than the air around it. What you are considering is more like an intercooler where to get any cooling benefit, the surface area is greatly increased. Imagine what little effect a straight aluminum pipe running along the front of your car instead of an intercooler would have.

Secondly, you will never cool the intake air below ambient temperature without an external coolant source. The best you can hope for is slightly above ambient. The term "cold air intake" assumes that there is some cold air outside the vehicle that you have access to.

 

[yunior]

don't knock it until you try it I have the same set up that wret has and as soon as I installed it you could definitely feel the power, no it does not get wet from the rain, yes it gets more than enough air to feed even the most demanding engines, and yes it does cool the temperatures quite a lot and this is speaking from experience. If you install the cold air intake, shield or what ever u want to call it drive around for 20 minutes and touch the cone filter, you'll notice it is cold to the touch, now try it with out the shield and touch it see what happens cant even keep your hand on it for more than a couple of seconds due to the extra heat of the engine.

 

[BGGSTin]

The difference seems to be miniscule though with final temps. taken into account, I mean if you use a comination of things CAI and sidemount you get x* with a short ram and front mount you can get close to that and with a short ram, front mount, and Ntercooler you can kill it. It's all really up to budget and your setup, everything has it's effeiciency ranges/benefits.
Thanks for educatin me on how it can make a difference, although miniscule, some say they can feel a difference so I'll believe you guys since I havn'e tried it.
Let's try to get some actual numbers to compare with different setups and see what works best. like :
1. Ambient temp. in engine bay
2. Temp. of intake air.
3. Temp. before intercooler but after turbo
4. Temp. after intercooler
Just a thought so we can find the best working setups and give some people ideas. Thanks for the info guys, hopefully we can get some temps.

 

[yunior]

The difference seems to be miniscule though with final temps. taken into account, I mean if you use a comination of things CAI and sidemount you get x* with a short ram and front mount you can get close to that and with a short ram, front mount, and Ntercooler you can kill it. It's all really up to budget and your setup, everything has it's effeiciency ranges/benefits.
Thanks for educatin me on how it can make a difference, although miniscule, some say they can feel a difference so I'll believe you guys since I havn'e tried it.
Let's try to get some actual numbers to compare with different setups and see what works best. like :
1. Ambient temp. in engine bay
2. Temp. of intake air.
3. Temp. before intercooler but after turbo
4. Temp. after intercooler
Just a thought so we can find the best working setups and give some people ideas. Thanks for the info guys, hopefully we can get some temps.

this is the desing I followed and the info he posted on this tread


4/16/03: The rest of this page now appears as a text-only FAQ,
please click Here for the photo album to make this a VFAQ.

Nearly everyone who mods a DSM will first hack or replace the highly restrictive factory airbox and air filter in favor of a lower-restriction air intake. While the basic goal of increasing airflow into the MAS is achieved, the temperature of the air passing through the filter increases at the MAS opening by 60-100F over ambient air temp. When this pre-heated air is then compressed, temperatures at the compressor outlet can quickly top 300F! Result: your car bogs massively whenever its hot out! Whether you've got a SMIC or a FMIC, you always want to keep the intake air charge as cool as possible.

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This $2 Airbox reduces my air filter temp. readings down to ambient air temperature out on the highway; and to between 2-12F above ambient in mid-Summer stop & go traffic. This is an absolute huge improvement over the 50-120F increase in intake air temps I recorded when I switched from the factory airbox to an open-element 'hot-air induction' system like most cars have!

By keeping the intake air temperature at the filter close to the ambient air temperature, you will feel an immediate improvement in your throttle response; and a palpable increase in performance over your existing hot-air induction system, with no other modifications whatsoever! Other nice side-benefits include: the reduction or elimination of heat-soak-induced vapor-lock and hard-starting when re-starting a turbo DSM after it sits for 15-30 mins. in the Sun on a 90+ degree day; and increased parts longevity :^)

Independent sources report that reducing the air intake charge temperature by 100F can result in an increase of 10 bhp. The 50-100F drop in intake temps. with this airbox in place can result in an instant 5-10 bhp increase over your existing heat-soaked open element system every day of the year! Not bad for $2 and a couple hours under the hood!

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DISCLAIMER: Check your local & state ordinances prior to installation. The author is not responsible for any failure or accident in any way related to the manufacture, installation, or usage of any parts developed from the ideas and techniques described herein on any motor vehicle licensed to operate on any public or private roadway or in any off-road usage.
*These designs and concepts are intended for DSM applications only. Any other usage is bad Carma ~;^(

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Material List:
a 12" x 18" piece of baseplate material
30" of 5/8" pipe insulation.
utility knife
thin cardboard (from a 12 pack of pop)
scissors
pencil
screwdriver
thick grease

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Baseplate Material:
Basically, any material which is both stiff and flexible(like sheet rubber) is suitable for the airbox sides. I used an 18" square sample of 3/16" thick radial rubber flooring, acquired from a local commercial flooring installation company. [there are several impact colors available from Johnsonite(www.johnsonite.com) and Roppe(www.roppe.com) if you want sheet rubber that color-coordinates with your silicone hoses.]
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Before you start:
Place the vehicle in park, and allow to cool. Safety glasses are only needed if you are prone to stabbing yourself in the eye with the pencil. Raise the hood. Disconnect the positive battery terminal(+).

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Fabricate the air box sides:
1) Temporarily fasten or locate the MAS; so that when the air filter is removed, the MAS will be held in place where it is located when the air filter is attached.

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2) Remove the air filter from the MAS.

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3) Measure from each side of the MAS to determine the distances forward to the headlight housing, rearward to the fusebox, downwards to the sheetmetal/shielded cable, and upwards above the hood line.

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4) Use the thin cardboard and pencil to mark the neck of the MAS on the cardboard, and cut out the MAS opening.

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5) Make a slightly over-sized cardboard baseplate by transferring the measurements from the MAS to the stationary obstructions(back/forth, up/down) to the MAS opening template made in step#4.

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6) Cut and fit the baseplate template to fit snug against the fusebox cover and headlight housing. Trim and fit the lower edge of the baseplate.

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7) At this point, you should have a cardboard template that fits front-back, and down, without any buckling. The hood line is the last side to trim down.

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8) Trim down the hood side to approximate the contour of the bottom of the hood. Lower the hood to about 2" above closed and sight inside with a flashlight to see the approximate shape. Trim as necessary until the template is a little taller than needed.

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9) Close the hood completely; then open and trim off any part of the cardboard crushed down by the underside of the hood. Continue trimming until the edge of the template is 1/8" to 3/16" lower than the underside of the hood; which allows space for the pipe insulation hood gasket.

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10) Complete 1-9 above for the endplate template which rests against the fusebox; cutting and fitting around the upper intercooler pipe, if so equipped.

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11) After you have completed both templates, transfer the outline of the template onto the radial rubber; and trim down to size with the utility knife.

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Install the fabricated back and side plates:
1) Fit the rubber parts in place; and reinstall the air filter onto the MAS.

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2) Place a 1/8" bead of axle grease on the top edges of the base plate, and lower hood. Raise hood and check for grease transfer to the hood. Trim down the top edge of the sides as needed, until no grease transfers to the hood.

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3) Use a single section of the pipe insulation to run from the fender to the front of the hood. To prevent bulking, cut the inside half of the insulation away at opposing 45 degree angles to create a 90 degree bend over the corner of the side and back plates.

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4) If you did a good job in fabricating, the pipe insulation now seals against the hood. If not, self-adhesive 1/4" thick foil-faced insulation can be applied on the underside of the hood to seal against the pipe insulation.

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5) If so equipped, remove the section of the hood edge rubber molding from above the RH headlight.This creates an intake venturi on the car's leading edge; which increases ambient temp air flow into the airbox.

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6) If you haven't already done so, remove the rubber cowl molding between the firewall and back edge of the hood to help cool down the entire engine compartment!

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7) Start car. Check for intake leaks. Enjoy the ride!

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Long Term Update: After about 30,000 miles, the rubber side panels warped. I used the panels as templates on a piece of 26 ga. galvanized steel; used tin snips to shape the sheet metal, and then adhered the sheet metal with contact adhesive to the filter side of the rubber panels. Adding this thin layer of sheetmetal raises the air filter temp by 1-2 degrees F above ambient in all driving conditions:




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Based on the above description, several design and fabrication modifications can be made to adapt the basic cold air box concept to different air filters/intake piping on virtually any car.



this can be found on http://www.vfaq.com/index-main.html