We're running an FC (88, AE per signature below) in SCCA auto-x and we might do some HPDE events. We currently have 10W30 Amsoil in the car (from the winter). We are upgrading our oil cooler lines to stainless and as part of the process, we are going to change the oil. We're new to rotaries so it is important to us not to make a mistake with the grade of Amsoil we choose. Our first inclination is to use 20W50 because of the warmer weather between now and September. We are worried that it might be too heavy. Please give us your suggestions.