Please see this earlier thread for a more complete description of the test procedure: https://bobistheoilguy.com/forums/t...rotection-volatility-results-nov-2024.389905/
In this paragraph, I will only point out things that differed. Oil temperature was ~380 F. The oils' initial oil weights were 0.850 grams. The total heating duration was 7 hours. The 7 hours does not include the time it took to cool the oils prior to weighing or to do the weighing. 7 hours provided sufficient data and VRP 5W-20 lost 16.5% of its weight by then, which is much more than the percentage lost in a typical engine over a typical OCI. I measured the weights after every hour but the plots show data only for hours 2, 4, 6, and 7 hours. The reason for that is that QS UD 10W-30 was losing mass at such a low rate, that actual weight losses per hour were approximately the same size as the scale's measurement error. Showing data only at hours 2, 4, 6, and 7 greatly improves the signal to noise ratio of the data, especially in the relative cumulative weight loss data.
Like in the other thread, Quaker State Ultimate Durability (QS UD) 10W-30 was used as the reference oil. The Valvoline Restore and Protect (VRP) 5W-20 was purchased in the United States a few months ago. As the graphs show, VRP 5W-20 is much more volatile than QS UD 10W-30, which I expected given that QS UD 10W-30 is one of the least volatile oils I've ever tested. More interesting is how its volatility compares to QS Ultimate Protection (QS UP) 5W-20 and 0W-20. VRP 5W-20 is more volatile than QS UP 0W-20. QS UP using majority or entirely GTL base oil is probably the main reason for that. Whatever VRP 5W-20's mystery ingredient is potentially is more volatile than the rest of VRP, so that could also play a role in the result. VRP has a bad smell that I've never experienced with any other virgin oil. Earlier in the test, that smell continued. After 6 hours of heating, I could no longer smell that foul odor in it, so apparently most of whatever causes that odor was gone.
Effects of measurement error on the cumulative weight losses decrease the longer the test goes. The bar graph of relative cumulative weight loss data is based on end of test weights rather than as a function of time like the other graphs. That minimizes the error of the data in the bar graph. Bar graphs have the virtue of simplicity and the weakness of concealing trends in the data and measurement error. Oil A will generally not be X times as volatile as Oil B, as the bar graphs simplify it to. Assume these are oils that have never been in contact with fuel and combustion byproducts. That ratio of volatilities will be a function of how much oil has already evaporated, the chemical/thermal reactions that have occurrred, what the temperature is, and other factors. If I left anything important out, please let me know.
In this paragraph, I will only point out things that differed. Oil temperature was ~380 F. The oils' initial oil weights were 0.850 grams. The total heating duration was 7 hours. The 7 hours does not include the time it took to cool the oils prior to weighing or to do the weighing. 7 hours provided sufficient data and VRP 5W-20 lost 16.5% of its weight by then, which is much more than the percentage lost in a typical engine over a typical OCI. I measured the weights after every hour but the plots show data only for hours 2, 4, 6, and 7 hours. The reason for that is that QS UD 10W-30 was losing mass at such a low rate, that actual weight losses per hour were approximately the same size as the scale's measurement error. Showing data only at hours 2, 4, 6, and 7 greatly improves the signal to noise ratio of the data, especially in the relative cumulative weight loss data.
Like in the other thread, Quaker State Ultimate Durability (QS UD) 10W-30 was used as the reference oil. The Valvoline Restore and Protect (VRP) 5W-20 was purchased in the United States a few months ago. As the graphs show, VRP 5W-20 is much more volatile than QS UD 10W-30, which I expected given that QS UD 10W-30 is one of the least volatile oils I've ever tested. More interesting is how its volatility compares to QS Ultimate Protection (QS UP) 5W-20 and 0W-20. VRP 5W-20 is more volatile than QS UP 0W-20. QS UP using majority or entirely GTL base oil is probably the main reason for that. Whatever VRP 5W-20's mystery ingredient is potentially is more volatile than the rest of VRP, so that could also play a role in the result. VRP has a bad smell that I've never experienced with any other virgin oil. Earlier in the test, that smell continued. After 6 hours of heating, I could no longer smell that foul odor in it, so apparently most of whatever causes that odor was gone.
Effects of measurement error on the cumulative weight losses decrease the longer the test goes. The bar graph of relative cumulative weight loss data is based on end of test weights rather than as a function of time like the other graphs. That minimizes the error of the data in the bar graph. Bar graphs have the virtue of simplicity and the weakness of concealing trends in the data and measurement error. Oil A will generally not be X times as volatile as Oil B, as the bar graphs simplify it to. Assume these are oils that have never been in contact with fuel and combustion byproducts. That ratio of volatilities will be a function of how much oil has already evaporated, the chemical/thermal reactions that have occurrred, what the temperature is, and other factors. If I left anything important out, please let me know.
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