I am a long time devotee of Ester Synthetics. I run Redline in my 2 trucks, and Maxima Extra in my 7 dirt bikes and ATV's. (If I were a racer looking to milk the most horsepower out of my engine, I would run the extremely slick Maxima Ultra.)
http://www.redlineoil.com/pdf/4.pdf
http://www.maximausa.com/technical/lubenews/LubeNews2002.pdf
For example, Redline 5W30 has a cSt @ 40 degrees C of 67, and a cSt at 100 degrees C of 10.9. That will give great cold starts, the oil is very "pumpable", the oil has a naturally high Viscolity Index (so not many if any Viscosity Index Improvers are needed), and it is 30 weight for tighter bearing tolerances.
OK, I know that sounds thin for a hot summer day, but get this, it has a High Temperature/High Shear (cP @ 150 degrees C) of 3.8! That's high enough to make "heavy" 40 weight. (30 weight and "light" 40 weight oils require a minimum HT/HS of only 2.9. "Heavy" 40 to 60 weight oils, require a minimum HT/HS of 3.7.)
So, if you are getting the picture I'm trying to pain here, with ester synthetics you can run a thinner oil that is very pumpable and won't bog your crank, yet in the bearings and on the hot wall of your cylinder, you are getting the protection of a heavy 40 weight.
BEST OF BOTH WORLDS! What more could we ask for???
[ February 03, 2006, 06:20 AM: Message edited by: Wayne Kelln ]