From digest.v7.n613 Tue Nov 18 19:49:58 1997
From: "Alan Alfano"<Alan.Alfano_at_SNET.com>
Date: Tue, 18 Nov 1997 15:31:54 -0400
Subject: RE: Opinions on synthetic oil filter (long)

>From: Harry Heck <72147.2025_at_compuserve.com>
>Subject: Re: Opinions on synthetic oil filter?
>Date: Tue, 18 Nov 1997 11:56:13 -0500
>
>Reply to post from: SRR <ritchie_at_knowware.net>
>Date: Mon, 17 Nov 1997 16:33:46 -0800
>Subject: Opinions on synthetic oil filter?
>
>I'm aware of 3 mfgs of synthetic element full-flow oil filters: Amsoil,
>HardDriver by Peak, and Mobil 1.
>
>They all claim finer filtration and higher flow, which is obviously a
>_good thing_. The higher flow rate is particularly advantageous when the
>engine is cold at start up and under high rpm conditions, when the
>pressure differential between the upstream side of the filter and the
>downstream side of the filter can reach around 14 psi or higher.
>
>Many factory and after market oil filters have an internal pressure
>bypass valve. When the engine is 'starving' for oil, the valve opens up
>and bypasses the filter element, dumping unfiltered oil back into the
>engine. A synthetic element oil filter with a high flow rate should
>minimize this occurrence.

Slight correction here.
IMHO The oil bypass valve opens when there is too much oil pressure, not when there is a pressure differential.
Excessive pressure occurs when the oil is like molasses (cold) or aggressive driving (high rpms) with 40 weight oil. The filter bypass is built into the oil filter itself. It is just a big spring and a flat plate that is at the end of the paper element. Without the bypass valve, the excessive oil pressure would blow out the paper filter element.
Then you would have 100 percent unfiltered oil, 100 percent of the time.

Just recently on the BMW Digest someone posted a note that a new high performance filter was just introduced by Mobil. I just surfed their web site and could not find any hard numbers. At the end of my post, I have included some of the Mobil 1 filter claims.

IMHO the Canton-Mecca filter set is the best. This filter has a cast aluminum housing with a replaceable and inspectable synthetic element. It is only for the M10, M42/44, M20 engines. I am surprised that more BMW fanatics do not buy this filter. The filter has 100% filter flow at ALL times.
Stock filters have a relief valve that allows unfiltered oil through at cold start up.
Aggressive driving with 40 weight oil will also cause the stock filter pressure valve to open letting unfiltered oil through. The Canton-Mecca filter burst strength is rated to 1000 PSI, with only a one PSI pressure drop.
This is the highest possible oil flow rate obtainable. It filters the oil to 8 microns, where the stock paper filters to 15 microns. I have used this set up on my 320i and 325e. The Canton-Mecca setup is expense.
I think the aluminum housing is aprox $90 and each element is $15. But this modification really does something, unlike the multi hundred dollar rear spoiler that is only useful at track speeds. (feel free to substitute your own under utilized $100+ accessory here)

Korman Automotive has tested and recommends this filter in their catalog. I have also seen it the latest BMP catalog. Regards,
Alan Alfano
alan.alfano_at_snet.com

BMW CCA #30492

1988 BMW 325iX
1956 Austin-Healey 100M (2)

Summary of announcement:
FAIRFAX, VA, November 5, 1997 -- Mobil Corporation today announced the nationwide introduction of Mobil 1 High Efficiency Oil Filters

Summary of claims:

the media area is 377 square inches, versus 363 square inches in the closest competitor.

demonstrated a 96.1 percent weighted average efficiency in removing damaging particles compared to an average of 82.07 percent (1) for conventional filters and 88.16 percent (2) for premium filters.

reached 601 psi before failure, while the nearest competitor failed at 303 psi.

resist hydrodynamic mechanical stress: 221,375 vs. 59,095 pressure impulse cycles to failure.

designed to withstand five times the normal system operating pressure of a typical automotive vehicle.