oil pressure / and coolant temp
Lets say 90 degrees ambient, avg humidity 50%.
Normal eng coolant temp on freeway..............190-210
Normal " " " on surface streets ....210-240(will be highest with a/c in traffic)
Normal oil pressure warmed up idle...15-30 psi
" " " cold idle 40+ drops as it approaches normal eng temp.
Oil pressure warmed freeway speed 30-60
" " cold " " 50-60
Oil TEMPS..........should follow coolant temp more or less except immediately after some hard running, hi rpm or heavy loading like long hills or extreme traffic. Oil temp goes UP during and after hard driving. its slower to return to normal than the water temp is. OIL is also part of the coolant system.. as it collects heat from the engines top end.
To understand what "high" means to your car and area, see the above and add 10 degrees to the ambient and that will mean that your eng temp will likely rise also, maybe not 10 but it will be higher. In winter where your eng temp is less likely to pass boiling, same adjustment, just down.
A SAFE high temp is probably no more than 250 with NO LOADING on the engine. I see 235 daily in the summer with the a/c in traffic @ 100 degree ambient. It drops to 195-200 shortly after moving again at 25mph or more..
The hotter it gets the less stress it should get. I have seen near 300 degrees and had no ill effects BUT I would not advise doing that. If it breaks 250 in an emergency I will try to shut down regardless of where....
Hope this helps, but its really dependent on the condition of the engine and the ambient.
Last edited by leesvet; Aug 28, 2013 at 10:30 PM.
Should I be concerned about 80PSI?
Thanks
Highway Driving (Steady state >50 mph):
Coolant Temp: 194F
Oil Temp: 204F
City Driving (Stead state <40 mph):
Coolant Temp: <200F
Oil Temp: 210 - 215F
Stop and Go:
Coolant Temp
<205F with AC ON
210 - 220F with AC OFF
Oil Temp >210, but I've never seen it >230F
If I get on it (rapid acceleration from a stop to highway speeds), then my coolant and oil temps both climb, but coolant quickly recovers down to the steady state temp. Oil temp takes significantly longer to recover.
This driving season I had a problem with my thermostat in that the coolant temp was running about 206F at highway speeds, but would drop down to under 200F when coming to a stop or steady state at under 45mph. Since this was new behavior for the car, I replaced the thermostat and the problem went away (confirming my theory that the old one was only partially opening).
This is on a stock LT1 with the exception of 4.10:1 gearing.
Steven
Last edited by WW7; Sep 1, 2013 at 10:22 AM.












