The best car performance upgrades for hot and humid weather in Grandview near Kansas City MO would be improvements to the car's cooling system, such as a high-performance radiator or a more efficient intercooler. Installing a cold air intake system can also help to improve the engine's air intake, providing cooler air for combustion. Upgrading to a more efficient exhaust system can also improve the engine's performance and reduce heat buildup. Additionally, window tinting and a good quality sunshade can help to keep the car's interior cooler. For more information, Please visit https://brattbrothers.com/services/.