I know the LT1 tends to run hot and how that is normal..why?
Thread Starter
Burning Brakes
Joined: Dec 2007
Posts: 805
Likes: 3
From: Waco TX
I know the LT1 tends to run hot and how that is normal..why?
Everyone says the LT1 was engineered to run hot. Just wondering why. Even with both fans running, etc. why does the engine run hotter than other engines? This is the only car I have ever had where the temp gauges actually moves once heated up. All other cars I have owned-the needle stays in one spot once warmed up-not matter how hot or cold outside and no matter how hard or easy I drive it.
On the LT1:
-Are the tunnels in the water jacket smaller than most engines?
-Are the fans weak compared to most engines' fans that run using the pulley?
-Smaller than average radiator?
-What other things make the engine run hot that are actually designed to make it do so (engineering things)?
I have told a 160 tstat will do nothing to combat temperatures in city traffic. Is that true?
On the LT1:
-Are the tunnels in the water jacket smaller than most engines?
-Are the fans weak compared to most engines' fans that run using the pulley?
-Smaller than average radiator?
-What other things make the engine run hot that are actually designed to make it do so (engineering things)?
I have told a 160 tstat will do nothing to combat temperatures in city traffic. Is that true?
Le Mans Master
Joined: Jan 2006
Posts: 6,564
Likes: 6
From: Woodstock Georgia
GM did it to lower emissions. The 160*F stat will make no difference in city traffic, the fan on/off temp settings are what matters. Lot of debating over the stock radiator cooling ability so I won't even go there.
Melting Slicks
Joined: Oct 2006
Posts: 2,238
Likes: 10
From: College Station TX
They run hot for 1 reason: they are programmed that way. The fans are electric, and reprogramming them for lower on temps will reduce traffic temps. My car with stock thermostat and stock fans will sit at 195 in traffic with both fans running (I wired them to switches so I can control them at will).
Team Owner
Joined: Sep 2001
Posts: 62,128
Likes: 1,727
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Every other car you own has a grill in the front to suck air through, the C4 does not. They are bottom fed, and their cooling air is hot off the pavement. There is no way for the temperature to stay down unless the thing is moving at speed. At idle, they will all go to their fan temperature setting no matter where it is and no matter what the stat is set at, if left alone long enough, assuming its not frigid outside.
In short, its an airflow/packaging problem.
In short, its an airflow/packaging problem.
Last edited by vader86; Jul 7, 2008 at 06:35 PM.
Supporting Vendor
Joined: Mar 2008
Posts: 1,762
Likes: 14
From: Cumming Ga
Everyone says the LT1 was engineered to run hot. Just wondering why. Even with both fans running, etc. why does the engine run hotter than other engines? This is the only car I have ever had where the temp gauges actually moves once heated up. All other cars I have owned-the needle stays in one spot once warmed up-not matter how hot or cold outside and no matter how hard or easy I drive it.
On the LT1:
-Are the tunnels in the water jacket smaller than most engines?
-Are the fans weak compared to most engines' fans that run using the pulley?
-Smaller than average radiator?
-What other things make the engine run hot that are actually designed to make it do so (engineering things)?
I have told a 160 tstat will do nothing to combat temperatures in city traffic. Is that true?
On the LT1:
-Are the tunnels in the water jacket smaller than most engines?
-Are the fans weak compared to most engines' fans that run using the pulley?
-Smaller than average radiator?
-What other things make the engine run hot that are actually designed to make it do so (engineering things)?
I have told a 160 tstat will do nothing to combat temperatures in city traffic. Is that true?
Cooler head temps will allow higher compression ratios with less emmisions. Then the hot water is flowed to the cylinder tubes leaving cylinder temp hotter than its previous versions. The hotter cyl walls is better on piston and ring wear. The lt1 also has a 2-way thermostat that is unique to the LT1 and is not interchangeable with older Chevrolet smallblock engines. This is particularly important if you decide to change to a colder 160 degree thermostat, make sure it is the proper dual acting type required by the LT1 otherwise it will run hotter because the bypass coolant cannot get back to the radiator.
Thread Starter
Burning Brakes
Joined: Dec 2007
Posts: 805
Likes: 3
From: Waco TX
Well, let me ask this...how many cooland sensors do most cars have?
I guess it is just psychological seeing the digital sensor be at 190 and the analog gauge almost pegged. Is it normal for the digital to read 194 and the analog to read around the 235 hash when I am in traffic and its 100* outside? Even when my A/C is on and both fans are running, the analoge gauge still gets to the 235 hash mark.
Maybe all engines get in the 235 range when the coolant has almost make it through the entire engine. Are most cars' coolant sensors at a place where the coolant is entering the engine? Hence, they will read a lower temperature and the gauge on your instrument cluster isn't almost pegged at the hot end?
Since most engines are not reverse flow, the heads are the last thing to get cooled. Would it be NORMAL for a car with a coolant temp sensors located in the cylinder head to read a 230-240* range?
I guess it is just psychological seeing the digital sensor be at 190 and the analog gauge almost pegged. Is it normal for the digital to read 194 and the analog to read around the 235 hash when I am in traffic and its 100* outside? Even when my A/C is on and both fans are running, the analoge gauge still gets to the 235 hash mark.
Maybe all engines get in the 235 range when the coolant has almost make it through the entire engine. Are most cars' coolant sensors at a place where the coolant is entering the engine? Hence, they will read a lower temperature and the gauge on your instrument cluster isn't almost pegged at the hot end?
Since most engines are not reverse flow, the heads are the last thing to get cooled. Would it be NORMAL for a car with a coolant temp sensors located in the cylinder head to read a 230-240* range?
Moderator Emeritus
Joined: Jun 2002
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From: Maryville Tn
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Every other car you own has a grill in the front to suck air through, the C4 does not. They are bottom fed, and their cooling air is hot off the pavement. There is no way for the temperature to stay down unless the thing is moving at speed. At idle, they will all go to their fan temperature setting no matter where it is and no matter what the stat is set at, if left alone long enough, assuming its not frigid outside.
In short, its an airflow/packaging problem.
In short, its an airflow/packaging problem.
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Team Owner
Joined: Mar 2001
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From: Boston, Dallas, Detroit, SoCal, back to Boston MA
I've got a racing radiator, electric waterpump, manual fan switch and a 160f stat. My car runs much better now.
The fans come on at the stock temps, when I'm not using the manual switch. It's for cooling down in the pits.
It actually does help in traffic, since it's not running as hot when the car's moving. It take that much longer to heat up.
The fans come on at the stock temps, when I'm not using the manual switch. It's for cooling down in the pits.
It actually does help in traffic, since it's not running as hot when the car's moving. It take that much longer to heat up.
Melting Slicks
Joined: Apr 2004
Posts: 2,764
Likes: 138
From: cyberspace NY
all engines run that hot. just your corvette has a digital temp guage.
there are millions of cars on the road that run that hot, and they are engineered to do so. only corvette owners try to defeat the factory engineering
there are millions of cars on the road that run that hot, and they are engineered to do so. only corvette owners try to defeat the factory engineering
Racer
Joined: Mar 2008
Posts: 389
Likes: 2
From: Austin Tx
They run hot for 1 reason: they are programmed that way. The fans are electric, and reprogramming them for lower on temps will reduce traffic temps. My car with stock thermostat and stock fans will sit at 195 in traffic with both fans running (I wired them to switches so I can control them at will).
In Austin traffic I get real nervous seeing 235-240 on the readout, even tho I'm supposed to be good up to 260ish.
Aggie Dad!
Melting Slicks
Joined: Oct 2006
Posts: 2,238
Likes: 10
From: College Station TX
Racer
Joined: Mar 2008
Posts: 389
Likes: 2
From: Austin Tx
Mojave - you weren't kidding about not being stock!
This also give me a clear idea of what the interior looks like nearly bare...never seen that before. Thanks for the pic.
