I'm going to be changing my thermostat on my 05 300C today or tomorrow and would like to go with a 180 or 190 thermostat. I currently have a custom exhaust and K&N CAI, but haven't been able to get a tuner yet. I will be getting one, but it likely won't be for a couple of months. Can I go with a 180/190 thermostat without a tuner? Thanks.