[angelo225544]

After researching aftermarket air intakes for my 1982 300D, I realized the stock air intake my son removed from his 2006 Honda S2000 looked very similar. I removed the stock air cleaner, and the S2000 intake fit right on! I'll take a photo tomorrow and see if I can include it. The intake consists of a simple plastic tube, about 24 inches long and with a 90 degree bend, at the end of which is a conical paper filter. I used the original Mercedes clamp to attach it to the turbo inlet, along with the original spacer ring. This is a MUCH more elegant design than the stock setup, but only time will tell how well it works. Here is my question: I ran a hose from the PCV vent in the valve cover DIRECTLY TO the air inlet tube, about 3 inches from the turbo inlet - is this OK? I have not yet installed an oil separator or catch can. I'm not sure if this is a recipe for trouble, since alot of oil vapor will be going directly into the turbo. Any advice will be appreciated.

 

[Zedd]

What made you decide to downgrade the intake?

There is no benefit to going to all that trouble, the only thing that will increase is noise. Also, power will likely decrease since the S2000 intake can't flow as much air as the stock system (200cfm vs 450cfm).

 

[winmutt]

Zedd is correct, the factory air setup is more than it will ever need. The only downside of it is the U bend.

 

[angelo225544]

What made you decide to downgrade the intake?

There is no benefit to going to all that trouble, the only thing that will increase is noise. Also, power will likely decrease since the S2000 intake can't flow as much air as the stock system (200cfm vs 450cfm).

I appreciate your response. I didn't make this change thinking I was improving performance, I just think the simpler design is usually the superior design. As far as decreasing performance, I'm not sure I understand your math. The S2000 motor is 2.2 liters and redlines at 8,000 RPM. This indicates that the S2000 requires greater air flow at full throttle than a 3 liter engine at 4,000 RPM. Further, that infamous 180 degree elbow on the stock air cleaner has been replaced by an essentially straight pipe of larger diameter. Please tell me where I'm wrong.

 

[dude99]

perhaps some pics of your setup could help clarify things

 

[winmutt]

I appreciate your response. I didn't make this change thinking I was improving performance, I just think the simpler design is usually the superior design. As far as decreasing performance, I'm not sure I understand your math. The S2000 motor is 2.2 liters and redlines at 8,000 RPM. This indicates that the S2000 requires greater air flow at full throttle than a 3 liter engine at 4,000 RPM. Further, that infamous 180 degree elbow on the stock air cleaner has been replaced by an essentially straight pipe of larger diameter. Please tell me where I'm wrong.

2.2*8000=17600
3*4000*1.75=21000

You forgot about the fact that at full boost you are flowing 1.75 * more than NA. Also comparing gas and diesel is apples and oranges. With gas you have to maintain stoich whereas in a diesel you can be all over the place with your lambda.

*fixed*

 

[dude99]

^^ I think you missed a zero on that diesel number....

 

[angelo225544]

perhaps some pics of your setup could help clarify things

I've included a photo. I wonder if the cfm flow rate being described is for a stock S2000 filter? The filter I used is a K&N E-1796 from a turbocharged 6.5 liter Duramax diesel engine. I haven't done the calculations, but it appears to have equal or greater surface area compared to the stock Mercedes filter. I can't imagine this filter on a 4" diameter inlet tube is going to restrict air flow. You'll also notice where the filter is located, as far as possible from the hot exhaust and turbo, directly under where the stock air intake would be. Now that I've had a chance to drive it, performance is definitely not negatively impacted - AND - I love the sound of the turbo spooling up and down. I feel like I'm much more in touch with what the engine is doing (I'm one of those purists who doesn't have a car radio, preferring to listen to my wonderfully engineered machine). I can now design and install a heat shield between the exhaust manifold/turbo and intake manifold, to slightly lower intake air temperature. None of this is an attempt to "hot-rod" my 300D. Instead, I'm trying to improve upon what many people consider the weak-link in this chain. Since the efficiency of any diesel is directly related to its ability to intake air, I think I've improved the efficiency of this motor, albeit only slightly.

 

[FratBoy]

2.2*8000=17600
3*4000*1.75=21000

You forgot about the fact that at full boost you are flowing 1.75 * more than NA. Also comparing gas and diesel is apples and oranges. With gas you have to maintain stoich whereas in a diesel you can be all over the place with your lambda.

*fixed*

I'm no mathematician, but did you count an intake stroke for each cylinder for each revolution? I think you need a "/2" in each of those somewhere...

The MB would still draw more air...

FB

 

[300Dman]

Concerning the Oil Separator; you do not want any liquid Oil hitting the Turbo Charger Compressor Wheel when it is spooled up.

Also folks have said that the K&N filters do not filter as well as the Paper Elments (lets more and bigger particles through); if so it ought to be less restrictive then it appears.

 

[angelo225544]

Concerning the Oil Separator; you do not want any liquid Oil hitting the Turbo Charger Compressor Wheel when it is spooled up.

Also folks have said that the K&N filters do not filter as well as the Paper Elments (lets more and bigger particles through); if so it ought to be less restrictive then it appears.

I'm going to install an oil separator tomorrow. Any oil that exits the valve cover is vaporized, but it immediately starts to condense as it flows through any tubing. An oil separator and its longer tubing ought to remove some, but not all the vaporized oil. The oil separator built into the stock air cleaner is also rudimentary, being nothing more than an empty can that causes some swirling of the gases, but most of the vaporized oil goes right through it. Since the oil that contacts the turbo is vaporized, my guess is that the centrifugal force at 100,000+ RPM allows it to self-clean. K&N filters do have larger pores to facilitate air flow, but they are also coated in oil, which is meant to capture particles that might otherwise pass through. From what I've read, a K&N filter has roughly the same air flow as a brand new paper filter, but while the K&N can be frequently cleaned, the paper filter will most likely complete its duty cycle, by the end of which it is significantly less efficient.

 

[Zedd]

The filter I used is a K&N

Ouch, get rid of that crapola filter while you still can!

ISO 5011 Duramax Air Filter Test Report

 

[neosama]

if you search around on the topic of crankcase gas filters you'll see a lot of people use a very coarse Stainless Steel filtering element aka a scrubbing pad. You can get them anywhere and you don't need very much at all. Best thing is they don't restrict flow very much when applied correctly. My setup has a 1-1.5 psi restriction which isn't too bad and didn't cause the valve cover gasket to leak.

 

[Zedd]

My setup has a 1-1.5 psi restriction which isn't too bad and did cause the valve cover gasket to leak.

Thats restrictive. -1 to +0.1psi is all there should be. More and you're risking the life of the turbo's oil seals.

 

[winmutt]

Ah I missed the bit that the S2000 was an aftermarket. Here I was thinking about asking the hw guy here to pop his hood so I could see it.

Not to mention its a hot air intake.

 

[neosama]

zedd...i bench tested my setup at work...didnt test it on the car so i'm not sure what type of restriction it actually pulls...more than likely not very much.

It only pulled 1.45psi restriction at volumes less than 100SCFH, since the benz is pulling way more under no load, I'm going to probably safely assume that the restriction the motor sees is far less.

Also, I don't know how you're measuring restriction. I used extremely accurate DP gauges or manometers when available.

 

[angelo225544]

Not to mention its a hot air intake.

I agree it's not a "cold air" intake, as ad copy writers have named them, but the stock air cleaner may be even worse. Consider: The stock air cleaner sits directly over both the exhaust and intake manifolds. This restricts cooling airflow over the intake manifold. Worse yet, the air cleaner itself acts as a heat sink. So, even though air is drawn in from outside, it is considerably hotter by the time it reaches the cylinders. This aftermarket air cleaner is drawing relatively cold air - remember the direction of air flow under the hood of a car - air directly behind the headlights is cooler than at the firewall. Intake air then goes directly to the turbo inlet, instead of being routed over the exhaust and turbo first. In my judgement, this setup should allow both the turbo and intake manifolds to cool more effectively, while keeping intake air in front of, rather than on top of the major heat source. Just my unscientific opinion - opposing views are welcome.

 

[angelo225544]

Ouch, get rid of that crapola filter while you still can!

ISO 5011 Duramax Air Filter Test Report

Interesting reading. Two things I wonder when I read reports like this: who sponsored the test, and are any of the measured differences meaningful, or merely theoretical? When unbiased scientific tests were done on motor oil performance (by consumer union), they found absolutely no difference in wear between ALL oils tested over 60,000 miles. Even the most expensive synthetic oils didn't outperform conventional oil, and doubling the change intervals had virtually no measurable effect on engine wear. Yet, we can all quote the marketing hype on the superiority of synthetic oil in reducing engine wear. My bet is that the K&N filter isn't as good as K&N says it is, and isn't as bad as their competitors would have us believe.

 

[cheapold280ce]

NIce Job looks really cool :goojob:

 

[angelo225544]

Thats restrictive. -1 to +0.1psi is all there should be. More and you're risking the life of the turbo's oil seals.

This sounds like good advice. I've noticed that any restriction at all in the CCV line causes oil sepage from my valve cover bolts. I'm going to run 3/4" tube into a water separator I bought at Home Depot. I removed the filter medium, which was designed to capture water, but will be too restrictive once its soaked with dirty oil. I was also considering putting some steel wool in my oil separator, but I think I'll skip it, as it can do alot more harm than good. This may also explain the very conservative stock oil separator design.