M1 Racing 4T is SH because it contains a fairly high concentration of ZDDP, around the 1300ppm mark i believe, but it's a very good oil, here in Europe we have Racing 4T 15W-50, no 10W-40, a friend of mine has run it in his TVR 3000M Race car ( Ford V6 with Triple Weber carbs ) and it is perfect and squeaky clean inside.
I think it should be perfectly fine.