Low temperature thermostat: Most new cars come with either a 180 degree or 190 degree thermostat. The thermostat opens the flowgate from the motor to the cooling system. By replacing it with a 160 degree thermostat the flowgate is opened sooner and begins to cool the car sooner and faster. Only drawback to this upgrade is that your heater in your car won't blow as hot. But the heater blow's red hot anyhow with the stock thermostat and I often never turn it up all the way unless I just got in my car and it's real cold. So 20-30 degree's lower is better anyhow. It will still heat up your car and keep you warm. There is a very little increase in horsepower, about 2-3HP. The real benefit comes when you add other product's to your car like the computer chip and K&N filter. Low temp thermostat's for the 3.4 are made by 2 company's. Hypertech at http://www.hypertech-inc.com or JETCHIP at http://www.jetchip.com and can also be ordered from JEG's at 1-800-345-4545. The part number for the Hypertech thermostat is 1005. Cost is $12.00 and requires partial draining of your radiator fluid to replace it.