A couple of notes about running fans:
1) Fans consume electricity, and therefore power (via the alternator)
2) The amount of power fans draw decrease with speed. If a fan is trying to pull air at 30 MPH, but you are traveling at 60 MPH, the fans are basically freewheeling and barely drawing any current.
3) Cooler-running engines tend to knock less, therefore able to make more HP at WFO (typically this requires tuning changes).
4) Cooler-running engines have slightly less efficient combustion during normal driving- giving higher emissions, decreasing MPG, letting your oils accumulate more moisture & volatiles (which typically are acidic), and wearing out your Catalytic Converter faster.
5) If your fans are running but not needed, that's wasted energy.
6) Most OEM electric fans draw somewhere around 2,000 CFM (I'm not sure of the exact spec's on our cars). At 60 MPH, your radiator is exposed to about 15,000 CFM. There is no need to run fans once you are at speed. Generally anything above about 25MPH is useless for fans.
7) If your fan is running but your thermostat is closed, you're probably wasting all of the energy required to power the fans. Fans are really only needed when the thermostat is 100% open and ambient moving air is insufficient to cool the contents of the radiator.
And a couple of other things to keep in mind:
1) The temp seen by the thermostat is not necessarily the same as the temperature seen by the computer via the thermocouple.
2) Cylinders 2 & 5 run hotter than cylinders 1,3,4, and 6 - because they are "surrounded" by other cylinders. But because detonation (preignition) is bad in any cylinder, these are the ones where you typically have to fight detonation. This effect is minimized with higher flow rates.
3) There is NO MERIT WHATSOEVER to the argument that "coolant is flowing to fast to be cooled off in the radiator". The faster the better, period end of story. Therefore a periodic flushing is a good idea on several fronts.
4) I've never seen a water pump fail in such a way as to cause a cooling problem (unless it is completely seized). This would require that the impeller is somehow broken or not functional. Water pumps are designed to start dripping long before seizure typically occurs.
5) Cooling needs of the A/C system are not necessarily the same as the cooling needs of the engine, so fans may run based on the need of the A/C system even though the engine doesn't need it.
6) In some of the cars I've had in the past (not sure about this one), cooling fans are powered down above XX MPH because they are useless (even when A/C is running).
7) Preignition / detonation can be somewhat controlled by fuel octane rating. I run 89 octane in summer because it cuts back on my knock dramatically.
8) Octane requirements of a given engine increase as it ages. This is typically because of carbon buildup that creates local "hotspots" which can pre-ignite the fuel mixture in the cylinder. This can be somewhat offset by running the engine cooler as well (i.e. 180-degree themostat), although my personal preference is to use higher octane.
So "will a 180-degree thermostat help me"? Probably not - it's mostly use to defend against knock as you try to extract more and more HP from your engine.
-BC