The 928 engine design is very good in many respects except one - Oiling.  The stock engines suffer from the dreaded 2/6 failure.  This happens when the oil pickup is no longer submerged, for example long sweeping left hand turns taken at high speed.  The G force causes the oil to be pushed back up the oil passages into the passenger side cylinder head leaving the oil level below the oil pickup.   The main reason this happens is that the original sump baffle was not effective.  Then there is the issue where the drivers  side oil drains are that they are aimed directly at the spinning counterweights, causing severe windage inside the crankcase.  (oil particles suspended in air)    The 928 engine also does not have a very good oil separator so that air ingested into the intake from the crankcase usually has a high volume of oil in it.  I decided to address both issues in my engine.  I incorporated a very comprehensive crankcase baffle, windage tray, as well as a crank scraper.  I also decided to improve on the factory oil separator.
Here is a pic of the crank scraper:

I decided to go with the version that contained teflon insets.  The reason for this was that I needed to trim the scrapers due to the differences between the stock rods and crankshaft counterweights.  I figured that trimming 4 separate pieces of teflon would be easier than trimming one continuous piece of steel.  (keep in mind there are 8 counterweights and 8 rods)


One of the problems with the 928 block is that there are 4 oil drains from the drivers side cylinder head that drain right onto the spinning counterweights for the crankshaft creating a huge windage problem. 

Here is a pic of one of the cylinder head drains:

Here is a pic of the oil drain deflector:

This collection of parts is mounted on the drivers side of the block.  The 4 L shaped pieces are the deflectors that keep the oil draining from the drivers side cylinder head from draining directly onto the spinning counterweights.  Notice that the oil deflector is multi layered steel, and is notched for my connecting rods.

Here is a picture of the oil pan and the GTS baffle which I installed in the last version:

The problem with the factory baffle is that it does nothing to keep the oil around the pickup during high G left hand sweepers.  Its also too low.  The oil level is actually above the baffle.
Here is a picture of the elevated baffle.   This is designed to work with the crank scraper and windage tray

In the above pictures I outlined parts that help diminish the amount of oil suspended in the air.  I also decided to minimize ingestion of oil suspended in the air into the intake.

Here is a pic of the factory oil separator..... if you can call it that... its really simple. 

Here is a pic of the modification for the oil separator.   Above the visible grate is a wad of course steel wool that will separate oil from the air as it passes thru to the intake.


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