My tired 300sd has a lot of blowby on the motor.. still runs fine though but it seems like lately a lot more oil has been coming out of the hole on top of the valve cover . Normally I wouldnt complain, but since its a california model, there is no oil return tube. I am usually stuck with a lot of oil stains on my driveway. I was thinking if i tapped a few more holes on the valve cover and ran like three tubes in stead of the one to the oil seperator, maybe less oil would come out of the holes on the valve covers. The idea behind this is that there would be less pressure, hence the blowby wouldnt be expelled at such a high force, resulting in less oil coming out.... any thoughts??

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take steel wool and pack it into the pipe this will allow it to still breathe and keep the oil in the valve cover, you can also put it in the breather pipe hope that helps ,some of the older models came like this. cause the oil to drip back ito valve cover instaed of blowing out.

wow thats a neat trick!! Thanks!!

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Also straight 40 weight diesel oil will seal the rings much better. No harm in warm weather. In fact with wear present just helps in general.
I can almost gaurantee it will lessen the blowby to some extent. I have seen it reduce oil consumption by about 1/2 on oil burners. That was compared to 15-40 oils. I also thought the steel wool was a good ideal. Why not use the two together?
If not time for an oil change yet you could add an oil thickner or viscosity increaser to the oil. Probably not as good as a straight 40 weight but might help. Do not develop using the viscosity increaser as a habit. Change up to a heavier oil.

Make it a road draft tube and vent it straight to the atmosphere.

Every 8 months, American cars drip as much oil as the Exxon Valdez spilled.