1987 190D 2.5NA OM602.911 air filter housing intake manifold modifications?! - PeachParts Mercedes-Benz Forum

bentrod · #1 03-18-2018, 04:20 PM

So I was reading up here and looking at my air filter housing and intake manifold.
Yes it has the EGR system and butterfly in the air filter housing ( the aluminum half - not the plastic cover, just to be clear )
All 5 cylinders are breathing from just one hole across a large flat area.
What's my question?
At one time I did see a 1983 190D 2.2, this car has no EGR system and its air filter housing ( once the air filter is removed ) is wide open with the 4 intake runners in view. Clearly better breathing. At least in this application.
So.....
Has anyone ever lets say took a hole saw and made 5 holes by the intake runners to improve breathing?
Also....
In the plastic half of the air cleaner housing I found a "restricted" plastic insert, that can be removed and does then revile full diameter air flow to the filter.
Is this restricted part used to reduce noise, or it does look like a venturi shape, perhaps to actually increase airflow to the engine.
I welcome your opinions!

bentrod · #2 03-21-2018, 10:19 AM

Here are some pics.

tjts1 · #3 03-21-2018, 12:15 PM

The airbox is designed primarily to reduce intake noise. If you are will to live with more noise and crank up the fuel then yes you can extract more power from it.

jay_bob · #4 03-21-2018, 12:36 PM

Also they create restrictions in the air flow to create a partial vacuum in the intake. This is necessary so the EGR can function.

Diseasel300 · #5 03-21-2018, 12:42 PM

With your foot to the floor, are you rolling coal (not a puff, but a black cloud)? If not, you're getting enough air as is and opening up the airbox or drilling new holes in the runners isn't gonna help you.

That flap is there to create a vacuum in the intake manifold to help EGR circulation. If the EGR is disabled you don't need the flap.

tjts1 · #6 03-21-2018, 12:51 PM

Quote:

Originally Posted by Diseasel300

With your foot to the floor, are you rolling coal (not a puff, but a black cloud)? If not, you're getting enough air as is and opening up the airbox or drilling new holes in the runners isn't gonna help you.

What if I told you can open up the intake, crank up the fuel and advance timing?

bentrod · #7 03-21-2018, 01:50 PM

Quote:

Originally Posted by tjts1

What if I told you can open up the intake, crank up the fuel and advance timing?

Go on!
I already got rid of the throttle butterfly and going to pipe plug the air box and exhaust manifold for the EGR piping.
I have no smoke at full throttle.
I would like a bit more power, say some exhaust smoke haze at full power.
I'm no fan of heavy black smoke - that's just wasteful and damaging to the engine and does not help our image.

Diseasel300 · #8 03-21-2018, 02:20 PM

Quote:

Originally Posted by tjts1

What if I told you can open up the intake, crank up the fuel and advance timing?

Of course you can!

The point remains valid: No smoke = adequate or surplus air for the fuel charge.

bentrod · #9 03-21-2018, 08:21 PM

Quote:

Originally Posted by tjts1

What if I told you can open up the intake, crank up the fuel and advance timing?

Would you be so kind to showing me the way to do so?! Thanks!

NZScott · #10 03-22-2018, 01:19 AM

Quote:

Originally Posted by Diseasel300

Of course you can!

The point remains valid: No smoke = adequate or surplus air for the fuel charge.

Yes, but the factory made the max fuel setting in the IP suit the air intake, not vice versa, so tweaking the fuel after intake mods should make more power.

bentrod · #11 03-27-2018, 01:42 PM

Can someone post the thread on how to turn up the fuel in this type of injection pump just a bit. Thanks!

Sorry - forgot to add.... with pics!

Diseasel300 · #12 03-27-2018, 01:51 PM

Not sure how much help it'll be, but I tuned the IP in my SDL last summer. It's a similar pump to the one in your car, not sure how identical it'll be since you have N/A. My quest was to increase the rev limit and decrease fuelling. My IP came out of a 3.5L and was irritating the hell out of me due to smoke and a low RPM cutoff. I do have a picture and a description of what I did in this post:
Help Tuning a 603 IP

tjts1 · #13 03-27-2018, 02:44 PM

Quote:

Originally Posted by bentrod

Can someone post the thread on how to turn up the fuel in this type of injection pump just a bit. Thanks!

Sorry - forgot to add.... with pics!

Check out the superturbodiesel forum. A lot of the information about modifying the IP settings also applies to NA.
http://www.superturbodiesel.com/std/showthread.php?tid=189

bentrod · #14 03-27-2018, 10:23 PM

Thanks!