Whatever oil you choose, you will benefit from
regular analysis. You can purchase the analysis kits from www.amsoil.com.
If you buy a preferred membership for $20 (1 year) you get 20%
off of all products. That's what you call cheap insurance. OaiTesting,
Inc. is the independent lab that does all the analysis.
Click on the image below to see a sample oil
analysis report:
.
I have been using AMSOIL 20w50 since I bought
my car in June 2000 and have been doing analysis about as long.
The oil filter I use is the AMSOIL EAO58
(formerly SDF-57) filter. These also have bypass and anti-drainback
technology, as with the OEM E30 M3 filter.
"Made with premium-grade full synthetic
media. Ea Oil Filters feature advanced full synthetic nanofiber
technology, making them the highest efficiency filters that are
available for the auto/light truck market. AMSOIL EaO Filters
are guaranteed for 25,000 miles or one year, whichever comes first,
when used in conjunction with AMSOIL Synthetic Motor Oil in gasoline
and diesel vehicles in normal service, 15,000 miles in severe
service."
Oil Change Interval Guide:
http://www.amsoil.com/lit/g1490.pdf
...... 
Bay Area ///Motorsport
2000-2008
