I've done the HP & FB deletes, air intake mods and am about to to the T/B bypass and install the Hypertech 160 degree thermo. I realize from what people smarter than me have said that I will not fully benefit from these mods before I can reprogram the PCM, but if I do the thermostat switch now will my engine be prone to overheating until I can do the PCM rprgrmg???

Im not sure what your stock thermostat is at.... 170 maybe....

Whatever you do, I would stay at what the OEM tstat temp was at... IF it overheats with the stock then you have problems, probably a waterpump or the radiator is clogged....

Im not sure what your stock thermostat is at.... 170 maybe....

Whatever you do, I would stay at what the OEM tstat temp was at... IF it overheats with the stock then you have problems, probably a waterpump or the radiator is clogged....
Alot of the performance-knowledgeable guys on this forum suggest replacing the stock 180 degree thermostat with a 160 because it allows the engine to run cooler and possibly up HP a little. But they also recommend getting the PCM reprogrammed when you make this and other changes; in this case the reprogrammed PCM will "tell" the cooling fan to come on sooner when necessary...:coolgleam

I'm not a mechanic and I don't play one on TV, but I would assume that a thermostat is triggered by the water temperature.

Since the temperature of the F-body thermostat is lower than the D-body, I wouldn't think over heating would be an issue.

Will you see any performance gain without adjusting the computer? Thats for the TV mechanic to answer. ;)

I dont see how that would give you any performance benefits.... I would leave it stock with the stock Tstat.... The radiator and fans in their current setup should be just fine in cooling it sufficiently..... With a 160degree stat you would be in warm up mode all the time....

Alot of the performance-knowledgeable guys on this forum suggest replacing the stock 180 degree thermostat with a 160 because it allows the engine to run cooler and possibly up HP a little. But they also recommend getting the PCM reprogrammed when you make this and other changes; in this case the reprogrammed PCM will "tell" the cooling fan to come on sooner when necessary...:coolgleam
Ahh, I forgot about the electric fan. That makes sense.

I dont see how that would give you any performance benefits.... I would leave it stock with the stock Tstat.... The radiator and fans in their current setup should be just fine in cooling it sufficiently..... With a 160degree stat you would be in warm up mode all the time....
Here you go Goldenboy:
http://impalassforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=005575

And it answers the original question, yes you can use the 160 degree stat, but no you won't see any performance gain until you reprogramm.

The layman answer. No