Grimmspeed 160 Thermostat

I have had this thermostat since when Rego rebuilt my motor towards the beginning of this year however never really had an appreciation for what it did for my car. I took a "journey" this weekend and had a pretty good cruise and I was monitoring everything about my car with the accessport. As some of you may know, the "rule of thumb" is that usually for every 10 degrees cooler your motor/coolant runs, its approx. a 1% gain in horsepower for your motor (obviously to an extent, as long as its safe for the motor and still benefits it rather than harms it). I remember in my WRX and in this STi, with the oem t-stat I used to average somewhere around high 180 degree temps all the way to high 190 degree temps when cruising on the highway in similar weather. This is normal for cars of our type.

During my weekend "journey", I logged my coolant temps for the entire time and while I was cruising I never went above 172 degrees (the point in which an oem t-stat finally opens to BEGIN cooling) and when stopping I never went over 190 while at a stand still where with the oem t-stat, I would frequent into the over 200 degree zone when sitting at a red light or slowing down. My average while cruising on the highway was actually around 165 degrees. For the price for the GS T-stat, I would definitely recommend it after watching its performance over a time test and the good thing is that if it ever were to fail, it fails open so that your motor will still have coolant running through it and to prevent it from overheating until you can purchase a new replacement.

http://www.grimmspeed.com/catalog/product_info.php?cPath=91&products_id=162

Nice, I need to get this, even though my thermostat is only under a year old.

I replaced my OEM thermostat that failed on my 04 wrx and I got another OEM and it failed again less than 2 months after i replaced it :-/