I probably would not mix oils. In the situation in Japan, I would use a
synthetic. There has been much disussion between myself and Mike Allison on
this subject. Mike is of the opinion that either the Castrol R or a good
multigrade oil is what you need.
The degree of research and the fact that Formula One cars all use synthetics is
a compelling argument. The only problem I see is that because synthetics are
less viscous, the "British Car Territory Marking Syndrome " is quite severe and
oil pressures usually run lower.
Rob Medynski, our resident MG specialist in Northern New Jersey, tells a story
of his M type blowing a rear oil seal and the engine running without oil for a
small period of time. When he did a tear down, he said the bearings ( babbit in
the U.S. equivalent to British "white metal" ) were totally
unscathed. He was of course running a synthetic racing oil which here in the
U.S. is considered to be better than Mobil 1 and is know as "RedLine". I
believe this oil is now run in several of the American LeMans series sports
class cars.
I do know once one uses the Castrol R (a vegetable based oil) in an engine,
you CAN NOT simply drain
and refill with a petroleum based oil.
For the amount of stress we place on our engines, I don't think it matters
much so long as the pan is kept topped up and it is changed frequently
although this is only my opinion.
The smell of the Castrol R though is never to be forgotten!!
Joseph
British Cars Web: http://www.team.net/sol
MMM list subscription info: http://www.team.net/cgi-bin/majorcool
|