I run 60/40 Dex cool in the 302 even though I hate GM, its works better then any other coolant. Friend had a Turbo car that ran 210-220 degrees all the time even with a 160 Degree thermostat in it. He put in Dex cool and it dropped his temp to around 190. The other day it was 104F here and even in traffic I was sitting at 180 degrees at the hottest, Truck sits at around 170 after its warmed up.