King320

Later this summer I'm going to have a cold air intake custom made for my car. I know all the controversy about "hot air intakes" but i think this idea will work. I went to a tuning shop in Johnson City, TN (home from college for a week) to get an estimate and ideas based on what im wanting to do. I've seen other intake setups on clks with the cone sitting near the engine itself, and in my experience (intakes on my old cars, Volvo s70 and Audi A4 2.8) those mainly give you a noise effect with minimal power gains so i want to go with a true cold air setup here. My idea is to have a 3" pipe mandrel bent to travel from the MAF until it bends down behind the headlight and sets the cone down behind the passenger side foglight. I think this gets the cone far enough away from the engine to allow for a significant temp. difference.


So, basically, start at the MAF (top pic) and go towards that light spot (like a 3/4 crescent) in the middle of the second picture (its a hole in the bottom of the under engine cover). The guys making the intake told me i'd need a bypass valve to catch any water that might get in through the cone. So basically the plan so far is:
1) Bend a 3" pipe to the necessary shape and weld on supports to connect to factory airbox supports (not chrome pipe, i plan to paint it flat black)
2) Intall open element air filter (type yet to be determined) and water bypass valve
3) Use a coupler to attach 3" pipe to MAF (i think the MAF diameter is 3 1/4")

Now questions...
1) Has anyone done this before? Any comments, advice?
2) Any recommendations on cone filters?
3) Do you think i should try to find a 3 1/4" pipe to get more air into the system or do you think that a 1/4 inch diameter reduction will cost me that much?

Thanks, ill keep you posted on the project. I think im going to do the install in July.

Josh K

Well if it went down into the fender then it technically would be a CAI and not a WAI. Don't go overboard on the pipe diameter - personally I wouldn't go bigger than a 1/2" over stock. You should definitely do the piping all the way to the engine - get rid of the rubber crap - one of the benefits of a CAI is that it provides a straighter, less obstructed path for the air. And a polished intake would look nice - don't be in such a hurry to flat black it. As for a filter, you can't go wrong with a K&N cone filter. And unless you plan on completely submerging the filter while you're driving, a bypass valve is completely unnecessary.

King320

1)I was talking about using a pipe that is smaller than stock, but maybe i should go with 3 1/2 inch pipe, the only thing is that this shop doesnt have a mandrel bending machine so they said it would be hard to bend it without crimping the inside of the turn. Think i should look for a shop with a mandrel bending machine?
2) Are you talking about adding more piping behind the MAF to the throttle body? I can see your point about smoothing the air flow.
3) They suggested the bypass valve since the cone is so low and i would be driving in the rain and could hit a puddle or something, BUT the valve is $40 and they could be trying to sell me something, what do you think? better safe than sorry?

Josh K

You can either look for a shop that has a mandrel bender, or you can just buy mandrel bends from a metal supplier. They have different radiuses available and you can get what you need and have it cut.

As for the bypass valve, you have to look at your weather situation - does your area get a lot of rain and are you often parked in the rain where the water level would be submerging the filter? If so, then you would need a bypass valve. If not, then you don't. Over here in CA we had a ton of rain this season. I have an AEM CAI on my daily driver/hooptee with no bypass valve and never had a problem.

midget fidger

cool, what college do you go to? for some reason i thought you were 17 haha

hellcat

He goes to Wake Forest.

midget fidger

ah ok what are you studying?

King320

haha, no just turned 20 yesterday. I'm majoring in Economics, minoring in political science, and since Wake doesnt offer a business minor im taking an accelerated business management program over the first half of the summer.

midget fidger

nice, i think i might have been confusing you with that kid who had a CLK55 and disappeared after a month or so

midget fidger

happy belated birthday too!

King320

thanks

str8ridin

I agree on the water bypass valve as well...you don't need it unless you submerge your filter in water. Rain/puddles that happen to find their way into the engine bay will evaporate with the intake temps. Hydro-locking is something that happens if you drive though a lake.

I'm a little disoriented from the pictures you posted, so I'm not sure if you have this set-up, but I would definitely consider sectioning off your engine bay where your filter will finally reside so that it effectively shields your filter from the hot engine heat. If that's not possible, I've seen cone filters now that come with cone heat shields that cover them. I think it is definitely worth while.

Also, painting your pipe flat black would absorb heat if I'm not mistaken. I would wrap it well with heat reflective tape to reflect as much heat as possible.

Remember, hot air is counterproductive for high flow filters. Some people actually lose power when they install cone filters or supposedly CAI. The SAE correction factor for hot air’s effect on engine performance is: For every 10 degrees you lower the intake temperature, you gain a 1% increase in power...and vice versa. And 1% of your overall HP is substantial. By effectively building a heat shield, filter shield and wrapping your intake pipe, you could lower your intake temps substantially, this freeing up substantial HP.

Also, don't forget the longer the tube with more bends and curves create harder intake suction pressure. Think of a long hose vs. a straw.

There is a whole science to building a better intake, but it also boils down to your car and engine set up. There is no exact science in my opinion.

Wow, that was the world longest post.

King320

yeh i can see how the pics are a bit confusing, the first pic should have been rotated 90 degrees to the left, so the way you're looking at it, the left is to the front bumper and the right side is to the rear. the second picture is looking down the front of the airbox from the front of the car.

VIPclk320

i ahve one on my car and very good results. here hiow it goes. i bought an AEM pipe for a 1993 civic hatchback with the DX motor almost the same bends as the clk engine bay. bought an hks filter and hooked it up to the AEM pipe.then you take off the air box and all the assemply for it it pops right out. the filter will sit right behinde the tow hinge on the front bumper behind the piece that pops out when you need to get the car towed. then driil very small holes on the black plastic that goes on the pop out plastic for more air flow to the filter. then loosen the clamps on the filter side of the mass sensor and buy a 4" to 3" (one side 3" inlet and the other side 4" inlet) intercooler hose and put one side around the edge of the air mass side where the stock airbox pipe conects to the ai mass sensot and clamps it with intercooler clamps and the other side to the AEM pipe and another clamp. and the filter will get air from the holes that you made and also the vents on the fender covers. and this instructions will cost you about $100 just kidding have fun with it and you see a bit of difference on way the car picks up.

Josh K

Good looking out! Nice to know of an existing AEM with similar bends to a 320. Kind of like how I had to get an accord AEM for my beater elantra. AEM filters are good as well.

FYI - the 3.2 motor will sound a lot more pissed off with a CAI... :0)

King320

Ha! great, because right now under slow acceleration it sounds like me waking up in the morning. and i hate mornings.

King320

That sounds like a great setup, would you mind posting a few pics?

str8ridin

So, you are using an intake pipe that has a diameter (3") designed for a 4 cylinder car?

Logic would say that, if you put a smaller attachment on a vaccuum cleaner, the "engine" would have to work harder to pull the same required air at the specific time becasue it is a smaller hole.

This seems counterproductive.

King320

I was somewhat confused about the 4" to 3" thing too (thus the picture request). The 320 has a MAF diameter of roughly 3" but i think its 3.25" in actuality. Really all you're doing is putting on a pipe of roughly the same size so im not sure that its a smaller attachment, i think what he's talking about tho is a 4" diameter on the AEM going to the 3" MAF. So it would give you a bigger hole to pull from. Also i dont think the AEM was necessarily designed for a 4-cyl as much as i was designed for the civic engine bay, when you buy an AEM intake you're really just buying a piece of bent pipe with some braces, paint, and stickers on it. The only thing that really relates to the engine size is the diameter of the MAF and throttle body (if you go for a full intake mod). Alot of N/A Audi guys tune 12V 2.8L V6 engines fairly successfully using big bore throttle bodies and MAFs, silicone hoses, and various after MAF intake setups. They actually use a japanese cone filter made by a group called Racing Sports Akimoto. Im not sure how far i'd wanna go with it, but ill probably get back on the audiworld 12v development forum and ask a few questions.

VIPclk320

you huys are right it's the 3 to 2 and it will fit the aem pipe. i would love to show you guys the pics but i ripped it out because of my turbo setup i'm using custom piping so now my charge pipe from the intercooler goes into the airmass. and i have a pipe that goes for the filter side of the turbine into a dual filter HKS setup.

King320

Do you mean the AEM pipe is 2" diameter? If you dont need it anymore email me some pics, i might be interested in buying it off you.

VIPclk320

it should still be in my friends shop. i'll look tomorrow because i'm going there to work on the intercooler piping for my turbo setup. if i can find it i will send you some pics. you can have it because i got it for free so i just pass the love around. if i can find it i'll i would charge you is just the shipping you can have the pipe because i need the filter i'm using it in my twin filter setup for the turbo. i'll let you know tomorrow.