[bmarty67]

I have 67 coupe w/ a 289CI stroked to 306. How hot is too hot for the water temp? I have digital gauges so the readout is exact. I usually run about 185-190, but while in continuous traffic and going slow it creeps up past 190-195. It has not gotten much past 195. I am just wondering how it is too hot for a water temp?

[Print Dad]

hello bmarty67,
You should be fine. Water boils at 212 so your OK.
If concerned too much drop to a lower size thermostat perhaps a 165.
You probably have a 185ish.

Enjoy the ride. Print Dad

[cindys_sn95]

maybe look a an electric fan also. v6 tarus fan is killer and cheap.

[Ivy66GT]

Originally Posted by Print Dad

hello bmarty67,
You should be fine. Water boils at 212 so your OK.

That's only if you run straight water without a pressure cap. With antifreeze and a working radiator cap the boiling point is more like 250F at sea level. Slightly lower at higher elevations: about 240F here in Albuquerque.

Anything below 200F in traffic is excellent. New cars run even hotter but they nearly all use an overflow recovery system on the radiator which is the major difference.

If your car is running 195F in traffic it will do so no matter what thermostat you use. The temperature difference between the radiator water and the outside air determines how much heat the radiator can reject.Water temp will go to whatever is needed to reject the heat the engine is generating or to the thermostat rating, whichever is higher. A 165 thermostat will only make it run cooler when you don't need it.