Summer Heat Driving
Thread Starter
Burning Brakes
Joined: Feb 2022
Posts: 818
Likes: 235
From: Bakersfield, CA
Summer Heat Driving
Good Day...I know, I know we shouldn't be driving our cars when ambient temps get to 100F+. I don't like to either but sometimes I need to. So I was thinking what would happen if I popped the hood but held it on by some clamping method? Sounds ghetto I know but what if? I am not thinking about running down the freeway at 90MPH but just around town with stop n go traffic. Downtown for me is like 10 miles down the road and on some of these HOT temperature days it gets to 220 by the time I get to town. So any suggestions or cautions about this theory? I read somewhere that it could lower the engine temp by as much as 15 degrees. Other suggestion was to cut the hood and install a louvre system but me not going to do that although I have seen some on this forum were brave enough to do just that. Thanks for any info. Cheers!!!
Safety Car
Joined: Jul 2010
Posts: 3,950
Likes: 386
From: Chandler AZ
Just drive it, 220 is fine, the low stage cooling fans kick on at 226, off at 219.
No need to open hood or modify it, just keep eye on coolant temp, and keep up on car maintenance.
I have had my car out well past 120, in Phoenix.
No need to open hood or modify it, just keep eye on coolant temp, and keep up on car maintenance.
I have had my car out well past 120, in Phoenix.
Drifting
Joined: May 2007
Posts: 1,550
Likes: 324
From: Mid Ohio
#1 thing to do is clean out the AC condenser and radiator. These C5's are like vacuum cleaners! (I just cleaned mine for the 2nd time last week and its amazing how much debris get up in the AC condenser)
btw, about 15yrs ago I did a bunch of thermal testing on hoods and under hood temps.
- Below 20mph it doesn't help w/a raised hood (rear)
- The air flows DOWN along the firewall and then out behind the wheels.
- The only advantage I saw (measured) was when at very slow traffic speeds and the e-fans running a full speed, the rear of the hood raised gives the hot air a place to go. But as soon as you get to 15-20mph the air reverses and started to flow downward along the firewall.
If I had to drive a C5 in heavy traffic and hot weather I'd get a larger radiator and higher flow fans. And.... keep them clean
btw, about 15yrs ago I did a bunch of thermal testing on hoods and under hood temps.
- Below 20mph it doesn't help w/a raised hood (rear)
- The air flows DOWN along the firewall and then out behind the wheels.
- The only advantage I saw (measured) was when at very slow traffic speeds and the e-fans running a full speed, the rear of the hood raised gives the hot air a place to go. But as soon as you get to 15-20mph the air reverses and started to flow downward along the firewall.
If I had to drive a C5 in heavy traffic and hot weather I'd get a larger radiator and higher flow fans. And.... keep them clean
Drifting
Joined: Jul 2004
Posts: 1,659
Likes: 683
From: Pingree Grove IL
My coolant temps never go over 190, I have a 160 or 180 thermostat, can’t remember, and custom tune, my fans turn on sooner then factory settings. But, as mentioned above, 220 is normal. I also have a trans cooler, even with my 3200 converter, trans temps don’t go over 180 on a hot summer day.
Team Owner
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I live in S Florida with humidity and temperature soaring into the 100 mark with humidity hitting high numbers, and it don't stop me from driving, and haven't had any overheating problems.
Le Mans Master
Joined: Dec 2017
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From: Virginia
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I don't know who told you you shouldn't drive if the outside temp is over 100, but that isn't true. The Vette is fine with coolant temps as high as 230, so you should be fine. The C5 was actually designed to run hot. As others have said, make sure that you clean your radiator and condenser. If your car is otherwise stock, you shouldn't have any issues. I highly recommend that you do NOT drive with the hood not properly shut. That's just asking for problems. If you're really concerned about the heat, swap out your OEM radiator for a Dewitts. They run around $800.00, but WILL lower your operating temps. The other option would be to tune your fans to come on at a lower temperature. Mine kick on at 199.
Pro
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From: Northern Ohio
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If you saw what cars go thru on the proving grounds during research and development and testing then driving in 100 degree temps ain't gonna hurt it.
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Racer
Joined: Apr 2021
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From: Texas
I was a little worried when I got mine, so I simply got a larger radiator which (to me) seemed to make a big difference. My old one was fine, my new one has temps about 10-15 degrees cooler.
Also, this might sound silly, but check your fans as well, the fuse can pop and no error will show on the DIC.
Also, this might sound silly, but check your fans as well, the fuse can pop and no error will show on the DIC.
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Unless you have problems with components in your cooling system, your C5 will do just fine in temps of 100+. As said, make sure your radiator area is clear of debris.
Race Director
Joined: Oct 2004
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I don't know who told you you shouldn't drive if the outside temp is over 100, but that isn't true. The Vette is fine with coolant temps as high as 230, so you should be fine. The C5 was actually designed to run hot. As others have said, make sure that you clean your radiator and condenser. If your car is otherwise stock, you shouldn't have any issues. I highly recommend that you do NOT drive with the hood not properly shut. That's just asking for problems. If you're really concerned about the heat, swap out your OEM radiator for a Dewitts. They run around $800.00, but WILL lower your operating temps. The other option would be to tune your fans to come on at a lower temperature. Mine kick on at 199.
I have a DeWitts, 160° stat, and my fans kick on@196°. OP can get a cheaper radiator, but he won't find a better one. He can install a $300.00 radiator, and wonder if it was a good choice, or install a DeWitts, and never think about the radiator again. Mine is 16 years old. The only time I've thought about it when I changed cams.......
Melting Slicks
Joined: Feb 2001
Posts: 2,803
Likes: 357
From: Northville, MI
Like others have said, have someone re-program your fans to turn on earlier and 225F is ideal for emissions. Personally I have my fans tuning on at 195/205 and I never have my water temps on the DIC, I have my oil Temps on the display, Th oil rarely go above 245F when autocrossing and 220 going down the highway.
Racer
Joined: Apr 2021
Posts: 289
Likes: 102
From: Texas
I know it's technically ok for the car to run at 220-230 but it's not my comfort zone, so I , like many, switched to a larger radiator. In my case, it was the cheaper ECP vs the Dewitts. With no other changes, it really dropped a lot of the temps. I ran it yesterday for example, it was around 108 outside, the highest it got, with air on was 205. i recommend.
Pro
Joined: Oct 2006
Posts: 515
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Two main problems with cooling are fan failure (mainly applicable to stop and go or standing still) and dirty radiator. I have seen both.
Nothing wrong with the 220 range. If there was, Chevrolet would have changed the fan activation temperature or other changes.
I have seen what is probably very near the design worst case, long uphill in Dearth Valley on a 120 degree day. Temp;s got to within about 5 deg of redline. Don't remember what the condition or radiator cleanliness was at that time.
Nothing wrong with the 220 range. If there was, Chevrolet would have changed the fan activation temperature or other changes.
I have seen what is probably very near the design worst case, long uphill in Dearth Valley on a 120 degree day. Temp;s got to within about 5 deg of redline. Don't remember what the condition or radiator cleanliness was at that time.