the lower the Noack = less burn off. Real synthetics are best + esters are best as they are used in jet engine oil. most oils get only a little if any ester in the blend as needed + even the best oils get a small amount due to $$$$. thinner oils + even thinner REAL synthetics are more prone to burn off as seen in the Redline spec sheets, + of course the finished oil with its better or just additives matter. the CST ii its viscosity-thickness at a spec temp 40C + 100C + it was shown on machinery lubrication that oils not being REAL synthetic thin more as heat rises + thicken a lot more in the cold + remember as oils are being used they react differently depending on base oils + additives. DI dirties + thickens oil much faster than port injection + of course fuel from the extreme DI thins it, so change it sooner especially if short tripping is common + IMO thinner oils are best left for extreme cold climates. in Pa i use 10-30's fake synthetics + my "loose TT 1.8T gets 15-40 + or 15-50 Redline in hotter months + i SEE higher vacuum on my installed gauge telling me it seals the best + lower consumption as boost passes 25 lb!!
