Its a 50/50 mix bought that way. Don't know much about tuning carbs. All brand new hoses, and for the eleventymillionth time, the bottom hose has a spring in it. Put the old 13lbs cap back on it. Fixed all cooling system leaks. Radiator has been flushed several times and no more rust. Don't know if I have air in the system, if I do how do i know? Brand new waterpump.