Originally Posted By: CATERHAM
Originally Posted By: OVERKILL
Originally Posted By: 901Memphis
Amoil OE series does typically have a higher NOACK than top synthetics, but its not their top product so it's obviously going to be weaker. All are under 15% with most good products falling in the 10% +/- 2% range, so its splitting hairs.
http://pqiamerica.com/March2013PCMO/Marchsyntheticsallfinal.html
In this 5w30 VOA comparison you can see that Amsoil OE has a NOACK of 10.9% while QSUD is 8.8% , PU is 6.6% and PP is 9.3%. Some are worse than OE, but with the exception of Lucas and CAM2 the worst is Havoline at 13% while most are even lower.
Once again we are focusing on one test that shouldn't even be a major factor in a 5.7 hemi since its not direct injection.
NOACK is not only important in a DI engine. Perhaps it is a
MORE important trait where DI is concerned, but less oil huffed up the PCV system in any engine is going to be of benefit in terms of intake tract cleanliness, PCV system life...etc.
That's true, but remember it wasn't that many years ago when the allowable NOACK percentage of an API oil was 25%! Now it's down to
If you're not seeing oil temp's consistently well above 100C I wouldn't give NOACK too much importance in your final choice of a motor oil.
For DI applications, the TEOST deposit test results (if you can get them) would be more relevant plus choosing a mid or low SAPS oil.
It is the baked-on atomized oil deposits in the intake tract that is the main issue in some DI engines.
True, but on a site where we obsess about these tiny differences, I did feel obligated to point out that this (reduction of intake tract deposits) is generally considered a benefit of a low-NOACK lubricant
I like to look back at my experience with Ford Windsor engines which seem to love, in EEC-IV trim, to get a nice film of goodness on the intake runners, inside the throttle body...etc. In my experience, utilizing a low NOACK lubricant (M1 0w-40 @ 8.8%) led to a SIGNIFICANT reduction in this trait.
The same observation can be made with respect to the Ford Modular engines, which vent the PCV into the intake, and the vent right at the throttle body, which leads to the throttle blade sticking and requires a cleaning of the throttle body. I've discovered that low-NOACK oils (M1 0w-40, AZO 0w-30) lead to having to clean the throttle body far less frequently.