What type/brand of thermostat can be used in an '85 308 ? What is the stock temp rating?
The "right" thermostat is one that you get from someone like a Ferrari dealer or T. Rutlands. If you want something local that will work with the same temp rating and size, but isn't as "heavy duty", then you can use one from a VW dealer that fits all Golfs/Rabbits 1980+, 180 degree, cost $12... or the Autozone equivalent p/n 437-180 $5.99. I personally think the heavy-duty one is worth the $35-45 price.
The 308 takes the same size thermostat as is used in a whole whack of other cars, including small block Chevy's. In my case I bought a Mr. Gasket brand high flow 'racing' Chevy thermostat from Jeg's for something like $8.00 or so. The thermostat has a much larger opening than does the OEM Ferrari type, and it is available in different temperature ranges if you wish. I selected a 165 degree one (... at least, I think that's what it was), and even with the 308's A/C on full bore on a hot summer's day, the car ran nice and cool. Highly recommended, and a cheap upgrade fix for a 308 which ends to run too hot!
No idea about the stock temp rating on the OEM thermostat, but most thermostats come in three flavors: 165 degrees, 180 degrees, and 195 degrees, so you pay your money and you make your choice. Me, I like the 165 one. - DM / Ohio
Check your OM -- e.g., page 61 of the US '84/'85 308QV OM: "...begins to open when the (coolant) mixture temperature reaches 176-185 deg F."
