Quote Originally Posted by kinyo View Post
true ... in a normally functioning cooling system, the thermostat dictates the operating temperature ... so if the TS wants to lower his temperature, he needs to change his thermostat with lower "opening temperature", not his coolant
Thermostats work using either a wax compound or a bi-metallic mechanism that reacts to temperature. Special alloys and formulations have been done for customized thermostats and its normally to defer opening rather than accelerate it. So unless you're in bed with someone who makes those mechanisms its highly unlikely to happen.

What you want to happen to get maximum overall cooling is to disengage the thermostat, upgrade your radiator, change your fan to one with a more aggressive blade geometry, and if its crank driven -change the pulley ratio. If the fan has a viscous clutch just engage it on high and keep it there (at the expense of power and economy).

The shell coolants are fine, nothing remarkable, they work, however 1-2 years you'll need to refill them depending on usage as the inhibitors lose efficacy around that time.

Avoid coolants that use an organic acid based inhibitor if you have a mixed metal loop (copper-brass radiator + aluminum engine + steel linings.