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re: #2, they did mention using an external oil pressure source to center the journals. Might be nice to have a valve and an accumulator for worrysome hypermilers to use just prior to restart
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Centering the journal with oil pump pressure is very involved. You would need oil holes with restrictors all the way around the crankshaft at every bearing. It is not going to happen in a car engine.
Accumulators however do exist for people who want to build oil pressure before they start the engine.
http://www.google.com/search?hl=en&q...or&btnG=Search
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re #1, they state the minimum thickness increases with surface speed, and decreases with load. My point here is that load increases in an engine with rpm as well, having to accelerate the pistons and overcome internal resistance. At lower RPMs the engine might not be making that much torque even.
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Why do you think the engine is not producing torque at low rpm? You could have wide open throttle and significant cylinder pressure, which translates to lots of torque, and large bearing loads, but the rpm is not high enough to produce enough HP to speed up the vehicle due to air drag at the speed you are currently going, or you are going up a hill, etc.
You will recall that (if you do not recall see this:
http://www.vettenet.org/torquehp.html)
HP = (Torque * RPM)/5252. (which by the way is why every graph you see of power in horsepower and torque in foot-lbs cross at the same rpm of 5252)
Or to put it another way, you can get the same HP at these two different engine operating conditions :
100 Ft-lbs of torque at 200 rpm, or 10 Ft-lbs of torque at 2000 rpm.
The bearing load on the crankshaft is lower at 10 Ft-lbs. torque.
As far as engine inertial loads being higher at high rpm, the loads increase as the square of the RPM. Thus they are only significant near the red-line rpm. At "normal" engine rpms the cylinder pressure loads dominate.
Another reason you would want an rpm high enough to get good oil flow volume out of the oil pump is that the bearings are COOLED by the flowing oil. The slower the oil goes thru, the hotter and thinner it gets in the bearing.
Look at this:
http://www.performance-auto-parts.co...nnecting-rods/
Also read this, look at the chart. Film thickness is zero at 180 rpm. They need to speed up that crankshaft!
http://130.15.85.212/proceedings/Wor...apers/A542.pdf
Finally here are pretty pictures of bearings that have been lugged.
http://www.mlcmotorfactors.co.uk/Tro.../BearingTT.pdf
http://www.hadmac.com/technical_info.htm