Originally Posted By: btanchors
Originally Posted By: Speak2Mountain
He's right. Lighter oils typically have problems in GDI w/fuel dilution and have a higher NOACK
Which property would be more predictive of resistance to LSPI - a higher flashpoint, or a lower NOACK? The reason I ask - Mobil won't say what the NOACK is of Mobil 1 Annual Protection 0W-20, but I note it has an unusually high Flashpoint - 242 degrees C, which equates to 467.6 degrees F. Isn't that unusually high for a Flashpoint for a PCMO in 0W-20 weight?
When the engine is running there is lots of oil mist/spray and combustion blow by in the engine crankcase I doubt the flash point or NOACK will make a difference in the real world. It seems better to have a viscosity cushion with fuel diluting engines as needed.