ok guys what are your secrets for your custom blends of oil. do you stick with same grades when mixing plain dino with synthetic? do you stick with same brands? What kind of ratio's are you mixing? i've been thinking of running a custom mix of my own. I'm planning on using regular Havoline Dino, mixing it with Havoline Full Synthetic. I plain on using 2 quarts of the Full Syn, and then 3.5 quarts of regular Havoline. Tell me what you think.