Alright, so my thermostat failed about a month ago, and finally got around to fixing it, so I brought my new thermostat to my mechanic and said he wouldn't need it cause he said he would cut the thermostat I already have and leave it half open just a bit, so coolant can constantly flow through engine without burning to much gas and stuff he said. He also mention that newer thermostats are to hard or stiff and that older engines can't withstand the pressure of newer thermostat and cause my engine to fail or blow a headgasket persay, and that I wouldn't need to have a newer thermostat cause I live in Florida and it gets to hot here already to be putting in newer thermostat, so he left it half open. While my another mechanic is saying that my I need to put in a new thermostat cause of other said issue that can happen or is happening, and that I should have one actually working. Can anyone give me ideas or what should I really do, cause last the thing I want to do is spend money on a new engine.