I wonder if that filter would work in my 300D. I'd like to install one of my bypass filters, since they've done so well at scrubbing the oil clean in my gas cars. At that point, I wouldn't really need the bypass filter built in to the cartridge anymore. Time to do some part number searching.

Does blocking the bypass return port offer any advantage, versus just leaving it open?

does it really matter...
 

for me, yes, it does. but it doesnt matter which one YOU pick for your car...

I dont use the wix because it doesnt have a bypass section.
I tend to go w/ mhyle or turkish fram...

I run syn @5k drians, going for an EOA this round.

So that's the filter that was in my 300D when I got it!!.. I always wondered about it not having a bypass section.

So I see all the numbers above and wonder if we are solely looking at filters for the OM617 ?

I have a Wix 51385 that was in a box of parts (Brand new perfect condition as best I can tell), but I am not sure what it is for. I have Bosch 1 457 429 274 and a MANN PF 1050/1 that are both for my 617, but they look different than the Wix. The wix is also taller by 25-30mm.

Any comment?

I am guessing that's going to be a problem. Not that I am real good with numbers!!!

The mentioned WIX is a 32 nominal micron Filter. For Details click on the Filter number at the below site.
http://www.wixfilters.com/filterlookup/ResultsPart.asp?PartNo=51385

On my Bypass Oil Filter setup I dirilled and tapped directly into the center of the Oil Filter Cap.
I did nothing to block of the Oil Return and Check Valve that are near the bottom of the long tube on the Oil Filter and Oil goes into the Bypass Oill Filter with no problems.
I use mostly Bosch Oil Filters.
The advantage to not blocking off the Check Valve/Oil Return is that the way my Filter is set up if the Bypass Oil Filter is plugged up the Check Valve is there to open up and allow the Oil to flow as it would normally.

You can see from the below pic that the Bypass Filter is clearly working (I left it in for 2 Oil Changes).
It is a 0.5 nominal micron string wound Filter.

I cannot speak to oil filters specifically but I design air induction systems and from what I have seen of air filters I would definately spend the extra dough for the good stuff.

Unlike the Oil Filters that some information is available on the micron level that they filter Air Filters seldom lest that information.
When I looked for that type of info I found a 3 Air Filters that listed that they Filter to 15 Nominal Microns. But, they were paper Element Filters that were for industrial purposes. Something like you might find on a medium sized Fork Lift.

This is just my though on it but I believe the same sized particles in the Oil will do more damage than the same sized particles coming in the Air Intake system.
The reason is that the Oil actually gets squirted and injected directly into the precision areas.
Only part of the Air with particles that goes into a Cylinder is going to make contact with the Cylinder Walls.
I believe that most of the particles in the intake Air are going to go out with your Exhaust gasses.

The problem with the intake Air is that you are always filtering new Air.
With the Oil the same Oil is passing through the Filter thousands of times so the Oil has a more chances to be clean than the Air does.
The intake Air only gets one shot at filtration.

We are getting off topic with the Air Filter issue. But, here is what I did.
Washable Air Filter and Intake Mod , With Larger Breather
http://www.peachparts.com/shopforum/showthread.php?t=280376

OEM filters are not designed to guarantee that all particles of a certain size are removed from the air. The specification is usually around 99.5% initial efficiency of ASTM fine dust.

ASTM fine dust has a range of particle sizes the smallest of which I recall being suprisingly large but I would have to look it up to be sure. However, some dust will always get through.

As the filter loads up it will trap smaller particles so it is a good idea NOT to change your filter too frequently. That is the most common mistake made with air filters.

Cheap aftermarket filters are garbage, the biggest problem being that the urethane seal usually does not do it's job thereby allowing unfiltered air right past the filter media.

K&N filters are meant to keep out small animals and children, nothing more. And no, they cannot possibly increase your horsepower by 5, especially after all that oil is transferred to your MAFS and turns your A/F ratio into garbage.

The good news? Do just as you did and clean your filter! We did a study a few years back and found that taking your dirty filter and whacking it on a table to remove the dust was nearly identical in performance to purchasing a brand new OEM filter. With a conical or cylindrical filter you could use compressed air from the back to blow it out. On most cars you could probably do this for the entire life of the vehicle.

And I think you're right, a bit of dust into the intake is much less harmful than in the oil for all the reasons you stated.

Sorry about the threadjack!

Why can't you run the WIX in a stock setup?

The wix 61X filter has a nominal filtration of around 40microns, and no bypass soot collector... I don't like them unless you run an aftermarket bypass setup.

John, thank you so very much for clarifying! :D Also glad to see you online. Still swamped?

See that now.

Looks like I should just stick to the Fram CH2930. Can't seem to get them locally anymore for some reason. Nervous ordering online, but figure if I stick to a reputable should be fine.

Anyone ever use a Fram CH4536? I've never seen one before, looks a bit different.