I have actually experienced this and can comment from my experience. I read that it is better for the car to have the 180 degree thermostat in it, so I tried it in both of my 3800 cars. One is supercharged,the other one isn't. If you do go to a 180 thermostat, it has to be one that doesn't have the little relief hole in it to keep air out of the system. There would be enough of a bypass to set a check engine light if it had the bypass hole. As for how the car drove? Heat was fine, not usually an issue in these cars. No check engine light. Temp on the gauge was a bit lower but didn't really seem to affect anything. Tranny stayed cooler for sure, because mine acts up as it heats up and that was definitely better. If your car tends to ping occasionally, it did remedy that in mine. Overall it did drive a little better, not much but there was a difference. I would say it had more mid-range torque probably due to not pulling timing from higher engine temps. What was a deal breaker for me, was that it cost me about 5 mpg. So since I drive drive a lot, the oem thermostat went back into both cars and fuel economy went back up instantly. So it is up to you, if you are having issues keeping it cool in a very hot area, such as Florida, then it might be a good idea to switch, may not even lose fuel economy there. If your vehicle is overheating , then you need to fix the problem , not mask it with a thermostat. This is all assuming you have taken care of the intake gaskets and upper manifold issue if that hasn't already been done on your car. * Just noticed you are in Illinois, unless you constantly sit still in traffic, you probably are better off staying with the OEM temp. Down south is a different story.
Last edited by 71Chevyguy; 03/15/19 05:32 PM. Reason: Noticed location.