ok ive spent a lot of money making sure my Trans Am doesnt over heat new radiator, water pump, fan clutch, thermostat, temp sensor and a kick @ss digital temp guage (highly recommend to all) any ways i ive in the UK and for the past couple of days been about 25oC / 77F now thats hot for us over here. With the new parts and everything the engine runs a a quite happy 71oC / 160 F (and thats without the heater on or the bottom fan suround which is going on tomorrow) am i over cooling as my normal day to day car which is 1 year old runs at 85oC / 185F or does that seem about the right temp for runnin this car?

G'day over there. I would say you are running a 160 degree thermostat. DiD you check the rating when you put it in? I'm running a 160 on my car to keep it a bit cooler, a 180 is standard i believe.

yeah 160 in it as i have had problems with other cars ive had overheating and dont want my new baby to have any problems when am out in her, i just wanted to make sure that she doesnt get any damage from undercooling thats if it is undercooling?

I like my car running around 180*.

160* is undercooling in my opinion, and ive found that the car takes forever to warm up in the winter with a 160* t-stat.

I ran a 160 on mine for a while and found that it never fully warmed up. Causing my car to idle faster and burn more fuel. I went to a 180 with a 185 fan switch and now the car idles fine. My mileage is better and the temp guage never moves (once warm). 195 was the standerd stat for my year.

I would use a min of 180, factory is 195. If you running to cool you may end up scuffing a piston or something. These engins are designed to run in the 180-220 range. If its running to cool you are wasting the chemical energy of your fuel to heat the combustion chamber. The quality of oil now days is part of the deciding factor in the tempature range you can run your engine in. I would suggest 180 at a constant and a good cold intake charge to get the best power out of your combo.