With a non counter weighted crankshaft, driving closer to above 4000 rpms
and bad things start happening to your bearing due to the crank flexing in
the center.  Accelerating quickly, (can it be done in a stock Vanagon?) also
causes the center of the crank to flex.

True the all aluminum engine case helps to prevent the pounding out of the
journals like the T1 engine, I think it causes the main bearing to wear and
causes the case halves to move under the stress rather than pound out.  That
is why when I rebuild my engine I had counterweights added to the crank to
balance out these forces.  My engine can rev at a higher RPM and not suffer
the same consequences as a stock WBX.  In fact it can go to 6500 rpm burst
and live happily.  The stock lifters pump up at @6000, hence the redline
below 5800.  I plan to put some performance lifters good to 6500 into the
engine (not to go faster but to make the engine work better, these lifters
are redesigned to be better.).

And I think that if you do not add counterweights when you add performance
enhancements, you are asking for trouble if you start driving it harder.

My 2 cents.

With that said, drive a stock WBX engine conservatively. Keep it under 4000
only go past 4000 on rare occasions.

Use the brakes to slow down, cheaper to replace a set of pads rather than a
tranny or an engine.

Keep it tuned up and adjusted correctly, otherwise it will be a slow death
to the engine and it struggles along.

  Less power = harder working = shortened engine life

Change fluids regularly

GET CORRECT TIRES, less rolling resistance=more power to push van=better
engine life and a SAFER van to drive.

Robert