Pablo,
With all due respect, a 20w-50 is at least one SAE grade too thick for a NEW, domestic V-8 engine, rebuilt to factory specs. The situation with your old, worn Volvo engine is not a good analogy. If this was a hand built, 326 ci small block putting out 525 hp and running 500 mile races, I might agree with you ....However, even those engines have have been running low viscosity synthetics for several years now - in the actual races - as Terry and George Morrison will confirm.
The 0w-20/0w-30 synthetics lower oil temps, generate more top end power, and can save you a refueling stop in the course of a long race ....
Buster,
The fact that the Cobra R recommends Mobil 1, 15w-50 has more to do with the high performance capability of the Mobil 1, xw-30 grades than it does with the engine ....
BTW, I now run the Amsoil S2000, 20w-50 year round in my 1990 Audi. However, the engine has 212,000 miles on it, and Audi recommended 20w-50 down to -10C/+14F in this motor. My oil analysis results clearly indicate the heavier oil is more desirable at this stage - when I post the comparison you'll see. The point is that you have to assess each situation on its'own merits and not make general statements.
[ November 20, 2003, 12:27 PM: Message edited by: TooSlick ]
With all due respect, a 20w-50 is at least one SAE grade too thick for a NEW, domestic V-8 engine, rebuilt to factory specs. The situation with your old, worn Volvo engine is not a good analogy. If this was a hand built, 326 ci small block putting out 525 hp and running 500 mile races, I might agree with you ....However, even those engines have have been running low viscosity synthetics for several years now - in the actual races - as Terry and George Morrison will confirm.
The 0w-20/0w-30 synthetics lower oil temps, generate more top end power, and can save you a refueling stop in the course of a long race ....
Buster,
The fact that the Cobra R recommends Mobil 1, 15w-50 has more to do with the high performance capability of the Mobil 1, xw-30 grades than it does with the engine ....
BTW, I now run the Amsoil S2000, 20w-50 year round in my 1990 Audi. However, the engine has 212,000 miles on it, and Audi recommended 20w-50 down to -10C/+14F in this motor. My oil analysis results clearly indicate the heavier oil is more desirable at this stage - when I post the comparison you'll see. The point is that you have to assess each situation on its'own merits and not make general statements.
[ November 20, 2003, 12:27 PM: Message edited by: TooSlick ]
