The oil system sucks on the stock Buick 3.8, so this is my shot at fixing it. Instead of the cam driven gear/shaft stock monstrosity, the later 3800 went to a much better crank driven gerotor oil pump.
Here are some pictures of my first try. I took the lower section of a 3800 front cover, hacked it off and mated it to the upper section of a stock 3.8 cover. The oil feed and supply passages all match the stock 3.8; the crank sensor bolts on but the mounting boss needs to be milled thinner. The "jig" used for welding was a spare block with a crank installed to locate the pump drive gear. I needed to make a dedicated jig so that the back side can be welded while it's still bolted down; I had trouble with this one warping at the weld points when I welded the back side.
I machined a jig out of plate steel with reinforcements on the back to fasten
and locate the cover halves while they're welded.
The next version utilized a dry sump stage two front cover for the top half.
It doesn't have the oil pump provision and is flatter on the lower section, making
the union a little easier. Here it is after my friend Tracy the TIG God welded it.
The original 3800 setup uses flats on the side of the lower timing gear to drive the
pump. I machined the balancer nose to drive the pump. I also had to space the
balancer out 1/4" and machine a matching spacer for the crank sensor.
The last picture is of the whole assembly installed after I had it powdercoated.
