Review on Mishimoto MMTS-WRX-01 Racing Thermostat for Subaru Impreza WRX/STI 2001-2017 by Christopher Smith

Very easy to install, WRX works fine and cool so far. Saw 3 cars overheating in traffic, I didn't even get halfway through. Addendum: About 3 months after installation I have more information to add. I would only recommend this for racing applications. For the daily driver, I had an issue with the CEL code going off because the engine coolant temperature was too low. On its own that might be fine, but combined with the Grimspeed cooler it prevents the car from reaching the correct operating temperature during normal driving, especially on motorways with fairly cold ambient temperatures (57 or so). Just a little additional information for those of you who are thinking about it. It still works exactly as it should, it just doesn't suit my application.