It has been many years since I used the Amsoil test kits, but comparing Amsoil to Blackstone- The Blackstone provides "universal" averages- i.e. average data on other customers engines. Amsoil (Oil Analyzers ?) did not. The Blackstone was $3-5 more expensive, but I thought it had more data. Both are good.
To the UA: Meh. You can tell if something is really wrongon a sample without them. The under-10 or 20 ppm of most metals is noise, for all intents and purposes, and having data that says "This engine averages 6 ppm but this other one averages 7ppm iron" is not really worth anything. You can build your own UA to your engine by getting it sampled every time and trending. Plus, its specific to your engine in your usage scenario.
[censored] calculates fuel dilution via open cup flashpoint. And the calculation is not the same across all samples. Its based on the flashpoint in the "Should be" Column. Some samples are >385F, others are >365F. Ive also seen >355F in the past. I haven't figured out yet what its based off of.
If your actual Flashpoint matches the Flash in the 'Should be' column, it will get labeled "Trace" fuel.
Every 20F below that is 1% fuel.
For example say your 'Should be' is >385F and the sample tests 385F, you will get told a trace of fuel was found.
If your sample tests 365F, you will get told 1% of fuel was found.
But lets say that instead of >385F as a should be, it was labeled >355F. The sample will be "free" of fuel. The same sample.
I feel strongly that [censored] fuel dilution is a guideline, at best, and you should probably ignore the fuel dilution % they put on and calculate based on a temperature of 380-400F depending on what your oil VOAs at. I think it loses accuracy very quickly beyond 2-3% also.(as if there was any to begin with...)This sample is a great example of this
Royal Purple, a synth oil comes back with a flash of 375F and "No fuel" but low viscosity. Sorry, no. There is Around 2% of fuel in there, but only my guess. Fuel by GC would tell for sure. Comments are talking about RP shearing as if it was just because its RP. It had a little help.
Polaris calculates fuel by GC, aka they are looking for the chemical traces of fuel in the oil and not guess-timating.
Plus you get TBN or TAN by default, along with Oxidation and Nitration.