The Mishimoto Racing Thermostat is engineered for drivers who demand more from their engines. High temperatures are the enemy of performance, and with this upgrade, your engine stays cool, efficient, and always ready for action. Whether you're ripping through track days, dominating backroads, or just want better reliability for daily driving, this thermostat is designed to open sooner than stock, allowing coolant to flow earlier and more efficiently. By keeping engine temperatures lower, you’ll experience stronger, more consistent power delivery, reduced stress on engine components, and improved long-term reliability.

Fitment Information

• Honda Civic SI EP3 & FG2 (2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011)
  
• RSX Type-S (2002, 2003, 2004, 2005, 2006)

Specs & Features

• Activates at a lower temperature so coolant flows through system earlier
• Allows for cooler engine temperatures
  
• Opens around 155 degrees (OEM is around 170 degrees)
• Fully Opens around 177 degrees (OEM is around 194 degrees)

Product Description

This genuine Mugen thermostat is engineered for better thermal control under high-demand conditions like track driving. It opens at a lower temperature than the stock unit to help maintain optimal engine performance.  The reduced opening temp helps minimize heat soak, prevent power loss, and ensure faster, more consistent warm-up and stable operating temp during spirited driving.