[Z06] Z06 Cooling
Thread Starter
5th Gear
Joined: Sep 2008
Posts: 5
Likes: 0
From: montchanin delaware
Z06 Cooling
I was just out driving and I noticed that my temp is at 203 and about 5 minutes later the fans must have kicked in and the temp went down to 193. When I got home I check the fans and they were running but when I shut the engine off the fans went off as well.
1st is a 10 degree differential normal. If it is normal than isn't that a big fuel economy issue?
2nd I thought the fans ran until the temp went down to whatever the thermostat is set for. What should the thermostat be set for?
1st is a 10 degree differential normal. If it is normal than isn't that a big fuel economy issue?
2nd I thought the fans ran until the temp went down to whatever the thermostat is set for. What should the thermostat be set for?
Race Director
Joined: Jan 2006
Posts: 10,554
Likes: 33
From: Not on either liberal coast.
What you're describing is normal. The car relies on incoming air (bottom feeder) to cool the radiator until the minimum temperature settings are reached. Your electric fans (x2) don't come on until 226 and 235 degrees. The car was engineered that way. And despite what some people will suggest about changing out the thermostat to a much cooler thermostat, it's not necessary for a street driven C5/Z06 unless your car is highly modified.
You may (mentally) benefit by altering the fan(s) on/off settings if you're of the old school thinking that all cars must run at 160-180 degrees. The settings can be changed by a tuner.
If you use search or search this forum (in the red banner) in C5 Tech, use keywords "electric fan settings" or similar for lots of informative reading about the technology of a C5/Z06 cooling system.
The higher temperatures used to concern me during AZ summers. I don't watch the coolant temperatures as much as I do the oil temperatures. I scroll to oil temperatures on the DIC/gauges and leave it displayed instead of watching my odometer. Summer time ambient air and heat rising from the roadway contribute to the problem.
I find my temperatures creeping up if I'm stuck in lots of traffic or in a lower gear on a winding mountain road. My oil temperatures have gone as high as 252 degrees. Once the traffic clears or I can get into a higher gear, the temperatures come down quickly. That's exactly what one should expect. If you find your temperatures don't come down, inspect the front of the condenser and radiator for debris. Since these cars are bottom feeders, they're notorious for picking up junk from the roadway (plastic bags, leaves, etc) which block incoming air flow to the aluminum radiator. A routine inspection and careful cleaning will eliminate that as a problem. You can also buy or DIY a screen to keep the larger junk from blocking the radiator.
You may (mentally) benefit by altering the fan(s) on/off settings if you're of the old school thinking that all cars must run at 160-180 degrees. The settings can be changed by a tuner.
If you use search or search this forum (in the red banner) in C5 Tech, use keywords "electric fan settings" or similar for lots of informative reading about the technology of a C5/Z06 cooling system.
The higher temperatures used to concern me during AZ summers. I don't watch the coolant temperatures as much as I do the oil temperatures. I scroll to oil temperatures on the DIC/gauges and leave it displayed instead of watching my odometer. Summer time ambient air and heat rising from the roadway contribute to the problem.
I find my temperatures creeping up if I'm stuck in lots of traffic or in a lower gear on a winding mountain road. My oil temperatures have gone as high as 252 degrees. Once the traffic clears or I can get into a higher gear, the temperatures come down quickly. That's exactly what one should expect. If you find your temperatures don't come down, inspect the front of the condenser and radiator for debris. Since these cars are bottom feeders, they're notorious for picking up junk from the roadway (plastic bags, leaves, etc) which block incoming air flow to the aluminum radiator. A routine inspection and careful cleaning will eliminate that as a problem. You can also buy or DIY a screen to keep the larger junk from blocking the radiator.
Last edited by hotwheels57; May 31, 2010 at 04:03 PM.
Burning Brakes
Joined: May 2010
Posts: 968
Likes: 3
From: Coplay PA
If you want lower temperatures, buy a 180 or 160 thermostat. You can also get an upgraded fan set but thats a lot more money then just a thermostat.
Hotwhels57 pretty much answered your questions but I'm just adding this as a suggestion, better fuel economy
Hotwhels57 pretty much answered your questions but I'm just adding this as a suggestion, better fuel economy
Thread Starter
5th Gear
Joined: Sep 2008
Posts: 5
Likes: 0
From: montchanin delaware
Thanks guys.
My old school training (pre computer control) was that actual temperature is not as important as how much it varies. If it is normal to run at 210 that is fine but if the temp varies 10 degrees the engine loses about 5 to 10% fuel economy. I'm not sure of the computer and what it may be controling. I'm not looking to second guess the designers but trying to figure out if I should just ignore the variation and trust the design or do I have a problem that I need to look at.
My old school training (pre computer control) was that actual temperature is not as important as how much it varies. If it is normal to run at 210 that is fine but if the temp varies 10 degrees the engine loses about 5 to 10% fuel economy. I'm not sure of the computer and what it may be controling. I'm not looking to second guess the designers but trying to figure out if I should just ignore the variation and trust the design or do I have a problem that I need to look at.
