Coolant Over Temp at First Track Day
Thread Starter
Intermediate
Joined: Aug 2015
Posts: 45
Likes: 6
Coolant Over Temp at First Track Day
The car is a 99 coupe, 6 speed, with wheels and tires being the only changes from stock.
Did my first track day today on a tight and twisty 0.9 mile kart track, and loved every second. I could only do about 5 laps at a time before the coolant would get too hot. My cooling system works great on the street, but it was boiling coolant today and by the end of about 15-20 laps, I got a low coolant warning from losing so much. I started the day at the high mark on the tank.
I flushed the system about a year ago, and I refilled it with prediluted dexcool/water blend. I usually see temperatures around 190 on the street, 230 in the summer with the A/C on, and today on the track it hit 260. Ambient temp was only about 85 today, so I'm worried about tracking the car once summer hits.
How can I keep it cool on the track? Do the antifreeze additives work? Do people run straight water at the track? Lower temp thermostat? Get a tuner and turn the fans on earlier/higher?
Did my first track day today on a tight and twisty 0.9 mile kart track, and loved every second. I could only do about 5 laps at a time before the coolant would get too hot. My cooling system works great on the street, but it was boiling coolant today and by the end of about 15-20 laps, I got a low coolant warning from losing so much. I started the day at the high mark on the tank.
I flushed the system about a year ago, and I refilled it with prediluted dexcool/water blend. I usually see temperatures around 190 on the street, 230 in the summer with the A/C on, and today on the track it hit 260. Ambient temp was only about 85 today, so I'm worried about tracking the car once summer hits.
How can I keep it cool on the track? Do the antifreeze additives work? Do people run straight water at the track? Lower temp thermostat? Get a tuner and turn the fans on earlier/higher?
Melting Slicks
Joined: Feb 2001
Posts: 2,804
Likes: 358
From: Northville, MI
Three things you can do to help with temps, among many other solutions. One is get a tune to have your fans come on around 190-195 low and 200-210 high, clean the debris from the radiator/AC cooler, and the most helpful, is run a lower gear, most go cart tracks you run in first and occasionally second, Running more in second will not slow your times as long as you are in you max torque range.
The LS1 engine peaks hp before 5700 rpm shifting into second at that time will put you around 3800 and higher torque. Keeping it in first gear only creates more engine heat and not faster timesl
The LS1 engine peaks hp before 5700 rpm shifting into second at that time will put you around 3800 and higher torque. Keeping it in first gear only creates more engine heat and not faster timesl
Melting Slicks
Joined: Sep 2008
Posts: 3,138
Likes: 802
From: Espanola New Mexico
IAs mentioned in the previous post, make sure your radiator and condenser are clean, take a garden hose or compressed air to clean them, also remove the cover and make sure there is nothing caught in between the radiator and condenser. Programing your fans to come on at a lower temp may help slightly, but the fans turn off once the car reaches 35 mph because a powered fan will restrict air flow.
Thread Starter
Intermediate
Joined: Aug 2015
Posts: 45
Likes: 6
run a lower gear, most go cart tracks you run in first and occasionally second, Running more in second will not slow your times as long as you are in you max torque range.
The LS1 engine peaks hp before 5700 rpm shifting into second at that time will put you around 3800 and higher torque. Keeping it in first gear only creates more engine heat and not faster timesl
The LS1 engine peaks hp before 5700 rpm shifting into second at that time will put you around 3800 and higher torque. Keeping it in first gear only creates more engine heat and not faster timesl
One more thing to note, elevation here is about 4600ft above sea level.
Last edited by C5YJ; May 3, 2020 at 02:50 PM.
Safety Car
Joined: Jun 2003
Posts: 4,510
Likes: 240
From: Coconut Creek FL
Look at getting a Dewitts dual core all aluminum radiator. Along with additional coolant capacity, the dual cores provide additional surface area for coolant to be cooled by the fans.
You can use it with your stock fans, or they also make some voluminous airflow fans you can add as well.
Radiator install on the C5 is a pretty easy job.
You can use it with your stock fans, or they also make some voluminous airflow fans you can add as well.
Radiator install on the C5 is a pretty easy job.
Thread Starter
Intermediate
Joined: Aug 2015
Posts: 45
Likes: 6
Look at getting a Dewitts dual core all aluminum radiator. Along with additional coolant capacity, the dual cores provide additional surface area for coolant to be cooled by the fans.
You can use it with your stock fans, or they also make some voluminous airflow fans you can add as well.
Radiator install on the C5 is a pretty easy job.
You can use it with your stock fans, or they also make some voluminous airflow fans you can add as well.
Radiator install on the C5 is a pretty easy job.
Drifting
Joined: May 2007
Posts: 1,547
Likes: 210
From: Huntersville, NC
no. for what you are doing, if you have no leaks, and clean the radiator you should be ok. The fans turn off at 35mph, normal, because if they were on at high speed, they would slow air flow.
So, coolant leaks are a big deal. They are an indicator your system is not holding pressure. At 15 psi, the boiling point is around 260 F for 50/50. If you aren’t at 15 psi, then you get nucleate boiling at the combustion chamber coolant area, which reduces heat transfer ability of the coolant dramatically.
I like to drain the system, remove the radiator and clean the outside of both the A/C condenser and radiator with the cleaner the home A/C people use on your AC condenser. Spray the stuff on, wait 5 minutes and wash with a garden hose. Then carefully pick the sand out with a dental pick. Sounds laborious, but worth the effort. Do not use a pressure washer!! you will bend the fins and restrict airflow.
After that, burp the system, and do not over fill. The system needs the head space in the reservoir tank. If you go water solid with no head space, the water pump will cavitate and flow goes way down when you need flow the most. The max fill line is embossed on the clear part of the tank in a place where mere mortals can’t see it.
So, coolant leaks are a big deal. They are an indicator your system is not holding pressure. At 15 psi, the boiling point is around 260 F for 50/50. If you aren’t at 15 psi, then you get nucleate boiling at the combustion chamber coolant area, which reduces heat transfer ability of the coolant dramatically.
I like to drain the system, remove the radiator and clean the outside of both the A/C condenser and radiator with the cleaner the home A/C people use on your AC condenser. Spray the stuff on, wait 5 minutes and wash with a garden hose. Then carefully pick the sand out with a dental pick. Sounds laborious, but worth the effort. Do not use a pressure washer!! you will bend the fins and restrict airflow.
After that, burp the system, and do not over fill. The system needs the head space in the reservoir tank. If you go water solid with no head space, the water pump will cavitate and flow goes way down when you need flow the most. The max fill line is embossed on the clear part of the tank in a place where mere mortals can’t see it.
Drifting
Joined: Sep 2009
Posts: 1,862
Likes: 595
From: Prescott, Arizona
My car is an A4 and I have tracked it for ten years. It is equipped with a DeWitts radiator with both transmission and engine oil coolers, B&M finned aluminum transmission pan, auxiliary transmission cooler, Improved Racing engine oil thermostat and SS braided oil cooler lines. I do not run coolant temperatures above 220 at Laguna Seca on a 90 degree day. I am happy with my setup.
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