Quote:
Originally Posted by bluesubie
The only difference between a 0W-30 and a 5W-30 is that the 0W is tested at -35C and the 5W is tested at -30C.
http://www.pqiamerica.com/coldcrank.htm
The second number is actually a viscosity range. You can have thin xW-30's (anything that meets GF5 specs) and thick wX-30's (anything that meets Euro specs or a race oil).
A Euro 0W-30 will be thicker at operating temp., have a higher High Temp High Shear, and likely have higher oil pressure than a GF5 5W-30. |
Agreed.
What I've gone so far as to do is google oils on my list with the term "VOA" in the search engine (like: "Mobil 1 0w40 VOA") and that way I can find out what the real 100C KV of an oil is and then I narrow my list and choose the oil that meets my desired 100C KV.
Example: the Mobil 1 0w40 was a bit thin for my use (<14 KV) but the Amsoil 10w-40 was ~14.5 KV.
Now I have to build a new car and I'm going to exclude the oil cooler. I anticipate a 20F increase in operating temp (from 260 to 280F) so therefore I will look for a thin-ish 50wt oil as to no lose my desired pressure at that heat range. I will probably look at 15.5-16.5 KV 50wt.