The 160 is the best choice for the summer months. That is what I run in the Car and Driver car, it prevents detonation, thus more power as the knock sensor doesn't pull timing. 180 for the winter months or it will run to cool. We keep both in stock http://www.howellautomotive.com

 

The 160 is best for track use where the 180 is best for all around everyday use.

 

180 plus the fan mod is just fine. i know people that run the 160, and i run the 180. with the fans on, there's no difference in operating temps at the line. why change out the thermostat when you don't have to?

 

Purple Ice is Royal Purple's coolent additive.

http://www.howellautomotive.com/inde...ROD&ProdID=204

Typically the engines will run around 170 with the 160 t-stat, because the stock radiator is not effient enough when the outside temps are higher. 180's typically run around 180. Now at high speed where you have large volumes of air moving through the radiator you will see the 160 equiped cars drop in temp. Datalogging shows this. On the C&D car on the 100 mph to 130 mph run, the 160 t-state helped play its roll, it keep the engine cool while under high boost. This reduced need for the computer to pull timing, allowing us to make max horsepower. We were a full 3 seconds faster on that part of the course than the 2nd place car, which was much lighter. Both keeping the engine cool, and the aircharge cool is key to making power.

 

And there you have it.
I got my Redline water wetter at Pep boys. Its even red like our coolant. Dropped my temps about 5 degrees. Nothing drastic, but it did help.