I am new to this board. I bought a Turbo car and the manual says to use fully synthetic 10w-30wt. I live in the desert and have always used M1 15w-50wt in hondas in the past with good results. I am tempted to use the 15w-15wt in this car after break in. or maybe use another brand of oil. not to sure about M1 10w-30wt. any suggestions?