An interesting fact: did you know the factory thermostat doesn 't start to even open until 186.8f and doesn 't fully open until almost 210f? did you also know that the new '09 dfi engines run a 176f thermostat? Or how about factory turbo, GT2, and GT3 engines that run with even colder thermostats from the factory? This low temperature thermostat, featuring a calibrated, German-made 160f thermostat pre-installed in a new, oe wahler thermostat housing and gasket, is calibrated to allow thermostat opening a full 20-25f degrees earlier than the factory thermostat. That means that the the low temperature thermostat is designed to be fully open by 180-185f, allowing for full flow to the cooling system to maximize cooling potential. Fits all 986/996 as well as 987/997 models to my2008. Replaces Porsche part numbers 996 106 125 52 (53). Does not fit my09 or later dfi or GT2, GT3, or turbo engines.