What is the normal operating temperature of our cars? Mine seems to run at 90celcius for awhile then slowly increases in Temp. Even when driving on the hi-way the Temp will creep up and run hotter than 90C. Yesterday it wasn't very far from the RED zone , then all of sudden it will drop back to 90C.

90 C is about normal for your car, but creeping into the red is NOT! Change to a 180 degree thermostat, and have your cooling system flushed. I suspect some blockages and poor flow. What does your radiator core look like? Is there any slop or noise in your water pump?

I will be definitely changing the stat. to 180. I flushed the system in the fall and the water pump was changed last fall .I think the core is ok, but I don't know for sure. How can u tell?: Also when changing the Stat, is the cooling system prone to airlocks? I noticed a bleeder screw...By the way: This is a great forum!!!

What'* 90C for us yanks?

90 C is 194 F

Robert Shaw has a "high performance" 180 t stat for our car that is available at Auto zone, I have only ever used stant superstats, but I tried this one and it works good. SLP also has lower temp t-stats that are nice quality.

GTX,
Do you have a PN?

194 is normal

On both of my supercharged bonnies, the temp usually remains around 195 degrees as long as the car isn't stuck in traffic, or it isn't a hot day, but that'* not always the case - sometimes they both operate at around 220 degrees (slightly to the right of the white tic line near the 1 o'clock position on the gage) even at freeway speeds when it'* 70 degrees F or cooler outside. Sometimes when that happens I turn on the AC to force both fans to turn on and that always brings the temp back down to around 195.

Most of the time the temp swings from 195 to 220 on both of mine. Isn't this nornal?

That'* normal for a stock setup. Not necessarily good. You need to get those temps down.