[madmaxx]

I noticed going down the freeway my coolnat temp reading was in my opinion low. I pulled the thermostat and found it to be 180F, the preferable temp. I put in a pan of water and noticed at 180F it opened. The interesting find though was even at 160F on the way down it was still open to some extent. I purchased a 180F and 195F Mr. Gasket balanced thermostats. I did the same test and got the same results. The opened at the correct temps yet did not close until 20F cooler than there set point. Since the SPF cooling system is so efficient it is very possilbe you can be going down the freeway and maintain a coolant temp less than 165F which as most know is very deterimental to engine life. Anything less than 180F an you experience accelerated cylinder wall wear. To futher test I drove on the freeway for 30 minutes and a constant speed to eliminate the possibility that it just takes longer for the thermostat to reduce it opening and maintain its temp.

Anyone know of a thermostat that closes near its opening temp in order to maintain the preferred coolant temp of 180F at all times?