HOT! HOT! Do any of you guys out west use 25 -120 W oil in the heat of the summer? I have been practicing in my 160 HP o-320 powered S 1C and the oil pressure tends to drops to the low part of the green arc but the oil temp only goes to about 220F. I have seen a publication somewhere that swows that 60 wt. oil can be used at temps over 80F. Here in Mississippi it gets up to about 100 to 105.There a lot of references in the literature to Lycoming service bulletin 1014, but I can't find a copy of it- I think it has the oil requirements and recommendations.