Is it necessary to buy Hypertech programmer to changing fan temp power-on? I want to purchase 160 temp thermostat but it doesn't make sense if you don't change temp at which fan comes on.

 

try and find a performance shop around you that can alter your pcm for a small fee. the hpp isnt worth the money. i had my fans programmed for 20 bucks. and while you dont HAVE to set the fans lower, its definantly recommended for the most benefit.

 

It's not absolutely "necessary" and I'd stay away from purchasing a HPP3 just for fans, unless you can find one used for cheap. You will run a little cooler at highway speeds with a 160. Already got a 180 in there, see you're in Evanston - if you're just looking to run cooler in the summer you can always purchase a manual fan switch. Also the gauge will read about the same, I have a 160 and temps set pretty low and stays just under 210 when warm unless it's really cold (by Florida standards).