With both fans running properly on my car, my cooling system barely goes above 220º. My car has the 3-layer radiator, new pump, thermostat, stainless overflow bottle, radiator cap, new hoses and the overheat protector. It does have a slight leak on the y pipe under the manifold. And my car is a dailydriver in 110º+ weather in the summertime. When the A/C runs is the only time the temp creeps above 220º. And even then, it still touches the 220 mark. The cooling fans normally kick on @ 220º, and will kick off @ 180º or so. The only time I've ever had the temp go any higher was when the water pump shut off (broken belt). Right now, my left front cooling fan has failed. To avoid slow cooling, and to keep performance, my otterstat has been bypassed, and a switch installed. This way my fans are fused to always run when the engine is on. I don't run my A/C right now because it will heat up my car too much. But with only 1 fan on constantly, my car runs cool. If your car starts creeping up to 240º, then I would say there is a problem. The first thing to check is how tight you alternator belt is. If it's loose, it could be slipping. Which in turn would not spin the water pump as quicky as normal. -Robert vin 6585