Originally posted by ajdulina:
5W-20 has no more or less protection than 5W-30. The last number only deals with viscosity at LOWER temperatures. High revs have nothing to do with it. However, a cold engine has more HP with 5W-20 because the crank can sling it around easier.
I suggest you read up a bit.
The first number is the oils weight at 0 degrees
The second number is the oils weight at operating temperature (210 degres)
The small the number the thinner (less protection, but better flowability) the oil has.
Also the stock oil pump has no problem flowing all the oil (5W30) out of the pan as is at high rpms.
My advice is to skip the thinner oil and stick with a true full synthetic like Mobil 1.
Not that it's true being both oils share the same weight when cold (5), but why would it matter if the engine had more HP when it's cold. You NEVER race an engine or put it under heavy load when it is not properly warmed up. That's a quick and sure fire way to shorten the life of your engine!
