Overheating & What You Can Do To Stop It

[ApexEight]

They totally shoulda shielded it from the factory. Wish it was more accessible, would be easier to wrap ourselves.

Sponsored

 

[DPL8]

People with multiple FWD track records and fast cars?

But to each their own...

HAHAHAHA

Facts...

 

[REDRAGN]

One cooling mod am counting on to offset the additional heat from the tune is the Dream hardlagged OEM water pipe replacement.

Curious if all have wrapped this bare pipe soaking heat from the DP? If not recommend doing something to this

I put gold foil tape on mine...easy and probably helps some. Its seen some heat!

 

[Gansan]

I hope you guys aren't pinning your hopes too much on insulating the coolant pipe. It's a big pipe feeding the water pump so there's little surface area compared to the volume of water flowing through it. The heat transfer is minimal compared to the multiple square meters of surface area of the radiator. Insulating it is one of those tiny last one percent type of details that won't magically fix anything.

 

[REDRAGN]

I hope you guys aren't pinning your hopes too much on insulating the coolant pipe. It's a big pipe feeding the water pump so there's little surface area compared to the volume of water flowing through it. The heat transfer is minimal compared to the multiple square meters of surface area of the radiator. Insulating it is one of those tiny last one percent type of details that won't magically fix anything.

I don't think anyone is pinning hopes on it. However, it is directly below the radiant heat of the turbo and behind the downpipe/cat and can benefit from deflecting as much of that heat as possible.

Its just another piece of the total cooling solution.

 

[fatherpain]

Thought I recently posted my cooling mod list here… but that must have been another thread.

Here it is for anyone interested. Bold are what I think is most important:

• Vented hood - J’s Racing or equivalent
• More open grill - J’s Racing or equivalent
• PWR Race radiator
• HKS Oil Cooler w/PWR/C&R upgraded core. DEI fire wrapped supply and return lines
• Dream Automotive Hardlagged OEM water pipe ideal or self wrap pipe
• Dream hardlagged DP or equivalent
• Dream hardlagged Turbo heat shield or equivalent
• Dream turbo oil return clamshell
• Acuity hoses
• Radium coolant expansion tank

With this setup, was able to complete all sessions with no cool down laps on a slow track Streets of Willow:

• last year in 103F minus the Dream OEM water pipe and turbo shield, on a scaled back tune on OEM HPFP
• Last week in 96F fully tuned with XDI 361 HP (probably a little more though) with mods listed above.

Could get an additional 20% airflow through the grill if remove center badge holder.

OEM temp gauge never moved off from normal.

No one single magic solution… but everything helps. Am interested whether Honda solves this with stock 2023 Rs or if still will be an issue.

 

[yargk]

I think we can make some basic back of the envelope calculations to learn more about CTR overheating. I found a great video. It’s a lap around sonoma raceway with a lap time of 1:55. That’s quick enough to overheat.

in 123 seconds, the car goes from
oil 237
water 204

to
oil 260
water 219

The oil increases 23 degrees while the water increases 15 degrees.

What to make of this?

If the car is overheating, then the engine is generating more heat than the oil coolers and radiators are dumping into the air.

For any cooling system, there are two parts, the part where the coolant takes heat from the engine and the part where the coolant dumps the heat. So in this system we can think about 3 aspects of the cooling system to improve, the direct oil cooling, the transfer of heat from the oil/engine to the coolant, and the cooling of the coolant.

1. Oil cooling through an oil cooler. Optimally this would be a fully ducted dual oil cooler setup (one on each side)
2. Improving heat transfer from engine to coolant. This can be improved by 3 ways I’d think,
   A. increasing the specific heat/thermal mass of the coolant (running more water in the mix)
   B. moving the coolant more (stronger water pump),
   C. keeping the coolant cooler which means that it will cool the engine/oil better and transfer heat faster from the engine to the coolant (heat transfer is proportional to temperature difference)
   I think this matters if the oil is overheating faster than the coolant.
3. Coolant cooling through a radiator to keep coolant temps in check.
   Get a bigger radiator, increase airflow through the grill, increase airflow out after the radiator (hood). (This sounds like 2 above, but is different in spirit, there we are talking about maximizing the transfer of the heat from the engine to the coolant and here we are talking about transfer of heat from the coolant to the air around the car. )

So we arrive at mostly the same list:
Dual oil coolers with excellent ducting
running a greater water to coolant ratio (60/40 water/coolant, or even more water with water wetter)
bigger, more efficient radiator (a 2nd radiator?)
more powerful water pump (is this possible?)
opened up grill
vented hood

What might be fun is that we can figure out how much extra heat per second is being generated.

Say the engine weighs 300 pounds, then in 123 seconds it goes up 23 degrees in the video above. And it’s aluminum. Let’s get this into better units:

135 Kg and 12.8 degrees C
The specific heat of aluminum is 903 J/kgC
so the energy/heat that builds in the engine is 1,560,384 J
The average heat per second is 12686 J/sec (watts) which is 16.9 hp.
(this number could be off, the part of the engine that gets hotter along with the oil might be less than 300 pounds, for instance. I don’t think accessories are increasing in temperature at the same rate)

What can we take from this odd number?

1. It explains why some drivers never see overheating and others who are just a little faster see overheating very quickly. A pro driver on a typical course is on the throttle a lot, say the duty cycle is above 60% of full throttle over the whole lap(might be more), then over the lap a CTR might be 200 hp on average (some time using 306 hp, other times coasting or braking), 40% of that goes into motion and 60% goes to heat. So 120 hp goes to heat. If you are on the gas a bit less, you could be generating 103 hp of heat and then not overheat (because we showed above that for the example lap the car was generating 17 hp of too much heat!)
2. 12.686 kw is about 43286.428756 btu/hr so that’s your extra cooling goal. If you can add cooling equal to half that number, it will take twice as long to overheat. It’s hard to estimate how much air flow you really get on track, but here are some example numbers for fixed oil coolers with fans for industrial purposes https://www.mcmaster.com/oil-coolers/
   It seems with a 50 degree difference they can cool 20,000 btu/hr with a 14 by 14 inch area, so maybe 40,000 btu/hr with a 100 degree difference? Seems like we’d need a bigger area than this though because of non-optimal airflow.

Thoughts?

 

[Lorre]

I think we can make some basic back of the envelope calculations to learn more about CTR overheating. I found a great video. It’s a lap around sonoma raceway with a lap time of 1:55. That’s quick enough to overheat.

in 123 seconds, the car goes from
oil 237
water 204

to
oil 260
water 219

The oil increases 23 degrees while the water increases 15 degrees.

What to make of this?

If the car is overheating, then the engine is generating more heat than the oil coolers and radiators are dumping into the air.

For any cooling system, there are two parts, the part where the coolant takes heat from the engine and the part where the coolant dumps the heat. So in this system we can think about 3 aspects of the cooling system to improve, the direct oil cooling, the transfer of heat from the oil/engine to the coolant, and the cooling of the coolant.

1. Oil cooling through an oil cooler. Optimally this would be a fully ducted dual oil cooler setup (one on each side)
2. Improving heat transfer from engine to coolant. This can be improved by 3 ways I’d think,
   A. increasing the specific heat/thermal mass of the coolant (running more water in the mix)
   B. moving the coolant more (stronger water pump),
   C. keeping the coolant cooler which means that it will cool the engine/oil better and transfer heat faster from the engine to the coolant (heat transfer is proportional to temperature difference)
   I think this matters if the oil is overheating faster than the coolant.
3. Coolant cooling through a radiator to keep coolant temps in check.
   Get a bigger radiator, increase airflow through the grill, increase airflow out after the radiator (hood). (This sounds like 2 above, but is different in spirit, there we are talking about maximizing the transfer of the heat from the engine to the coolant and here we are talking about transfer of heat from the coolant to the air around the car. )

So we arrive at mostly the same list:
Dual oil coolers with excellent ducting
running a greater water to coolant ratio (60/40 water/coolant, or even more water with water wetter)
bigger, more efficient radiator (a 2nd radiator?)
more powerful water pump (is this possible?)
opened up grill
vented hood

What might be fun is that we can figure out how much extra heat per second is being generated.

Say the engine weighs 300 pounds, then in 123 seconds it goes up 23 degrees in the video above. And it’s aluminum. Let’s get this into better units:

135 Kg and 12.8 degrees C
The specific heat of aluminum is 903 J/kgC
so the energy/heat that builds in the engine is 1,560,384 J
The average heat per second is 12686 J/sec (watts) which is 16.9 hp.
(this number could be off, the part of the engine that gets hotter along with the oil might be less than 300 pounds, for instance. I don’t think accessories are increasing in temperature at the same rate)

What can we take from this odd number?

1. It explains why some drivers never see overheating and others who are just a little faster see overheating very quickly. A pro driver on a typical course is on the throttle a lot, say the duty cycle is above 60% of full throttle over the whole lap(might be more), then over the lap a CTR might be 200 hp on average (some time using 306 hp, other times coasting or braking), 40% of that goes into motion and 60% goes to heat. So 120 hp goes to heat. If you are on the gas a bit less, you could be generating 103 hp of heat and then not overheat (because we showed above that for the example lap the car was generating 17 hp of too much heat!)
2. 12.686 kw is about 43286.428756 btu/hr so that’s your extra cooling goal. If you can add cooling equal to half that number, it will take twice as long to overheat. It’s hard to estimate how much air flow you really get on track, but here are some example numbers for fixed oil coolers with fans for industrial purposes https://www.mcmaster.com/oil-coolers/
   It seems with a 50 degree difference they can cool 20,000 btu/hr with a 14 by 14 inch area, so maybe 40,000 btu/hr with a 100 degree difference? Seems like we’d need a bigger area than this though because of non-optimal airflow.

Thoughts?

I’m lost after the first few paragraphs. Lol!

 

[Unity Performance]

Thought I recently posted my cooling mod list here… but that must have been another thread.

Here it is for anyone interested. Bold are what I think is most important:

• Vented hood - J’s Racing or equivalent
• More open grill - J’s Racing or equivalent
• PWR Race radiator
• HKS Oil Cooler w/PWR/C&R upgraded core. DEI fire wrapped supply and return lines
• Dream Automotive Hardlagged OEM water pipe ideal or self wrap pipe
• Dream hardlagged DP or equivalent
• Dream hardlagged Turbo heat shield or equivalent
• Dream turbo oil return clamshell
• Acuity hoses
• Radium coolant expansion tank

With this setup, was able to complete all sessions with no cool down laps on a slow track Streets of Willow:

• last year in 103F minus the Dream OEM water pipe and turbo shield, on a scaled back tune on OEM HPFP
• Last week in 96F fully tuned with XDI 361 HP (probably a little more though) with mods listed above.

Could get an additional 20% airflow through the grill if remove center badge holder.

OEM temp gauge never moved off from normal.

No one single magic solution… but everything helps. Am interested whether Honda solves this with stock 2023 Rs or if still will be an issue.

We'll be offering Dream Automotive products very soon, so it's great to see you've been able to utilize a number of their parts towards your solution!

 

[Lust]

I think we can make some basic back of the envelope calculations to learn more about CTR overheating. I found a great video. It’s a lap around sonoma raceway with a lap time of 1:55. That’s quick enough to overheat.

in 123 seconds, the car goes from
oil 237
water 204

to
oil 260
water 219

The oil increases 23 degrees while the water increases 15 degrees.

What to make of this?

If the car is overheating, then the engine is generating more heat than the oil coolers and radiators are dumping into the air.

For any cooling system, there are two parts, the part where the coolant takes heat from the engine and the part where the coolant dumps the heat. So in this system we can think about 3 aspects of the cooling system to improve, the direct oil cooling, the transfer of heat from the oil/engine to the coolant, and the cooling of the coolant.

1. Oil cooling through an oil cooler. Optimally this would be a fully ducted dual oil cooler setup (one on each side)
2. Improving heat transfer from engine to coolant. This can be improved by 3 ways I’d think,
   A. increasing the specific heat/thermal mass of the coolant (running more water in the mix)
   B. moving the coolant more (stronger water pump),
   C. keeping the coolant cooler which means that it will cool the engine/oil better and transfer heat faster from the engine to the coolant (heat transfer is proportional to temperature difference)
   I think this matters if the oil is overheating faster than the coolant.
3. Coolant cooling through a radiator to keep coolant temps in check.
   Get a bigger radiator, increase airflow through the grill, increase airflow out after the radiator (hood). (This sounds like 2 above, but is different in spirit, there we are talking about maximizing the transfer of the heat from the engine to the coolant and here we are talking about transfer of heat from the coolant to the air around the car. )

So we arrive at mostly the same list:
Dual oil coolers with excellent ducting
running a greater water to coolant ratio (60/40 water/coolant, or even more water with water wetter)
bigger, more efficient radiator (a 2nd radiator?)
more powerful water pump (is this possible?)
opened up grill
vented hood

What might be fun is that we can figure out how much extra heat per second is being generated.

Say the engine weighs 300 pounds, then in 123 seconds it goes up 23 degrees in the video above. And it’s aluminum. Let’s get this into better units:

135 Kg and 12.8 degrees C
The specific heat of aluminum is 903 J/kgC
so the energy/heat that builds in the engine is 1,560,384 J
The average heat per second is 12686 J/sec (watts) which is 16.9 hp.
(this number could be off, the part of the engine that gets hotter along with the oil might be less than 300 pounds, for instance. I don’t think accessories are increasing in temperature at the same rate)

What can we take from this odd number?

1. It explains why some drivers never see overheating and others who are just a little faster see overheating very quickly. A pro driver on a typical course is on the throttle a lot, say the duty cycle is above 60% of full throttle over the whole lap(might be more), then over the lap a CTR might be 200 hp on average (some time using 306 hp, other times coasting or braking), 40% of that goes into motion and 60% goes to heat. So 120 hp goes to heat. If you are on the gas a bit less, you could be generating 103 hp of heat and then not overheat (because we showed above that for the example lap the car was generating 17 hp of too much heat!)
2. 12.686 kw is about 43286.428756 btu/hr so that’s your extra cooling goal. If you can add cooling equal to half that number, it will take twice as long to overheat. It’s hard to estimate how much air flow you really get on track, but here are some example numbers for fixed oil coolers with fans for industrial purposes https://www.mcmaster.com/oil-coolers/
   It seems with a 50 degree difference they can cool 20,000 btu/hr with a 14 by 14 inch area, so maybe 40,000 btu/hr with a 100 degree difference? Seems like we’d need a bigger area than this though because of non-optimal airflow.

Thoughts?

The oil temp reading from the aim solo 2 DL is not actually oil temp. I keep telling people that this is reading fuel temp instead. Because AIM doesn’t have a profile for the FK8, people use the fk2 instead.

 

[yargk]

The oil temp reading from the aim solo 2 DL is not actually oil temp. I keep telling people that this is reading fuel temp instead. Because AIM doesn’t have a profile for the FK8, people use the fk2 instead.

Thank you, I haven't followed as closely as I'd like. Do you know in your data how fast oil temp goes up over a lap? I'd be happy to redo the numbers.

I know others have posted oil temp vs. time as well, I'll look around.(of course it only helps if they have the pace)

 

[fatherpain]

That is super, super cool. Might have to hit you guys up as new products become available.

Have posted DIY installation posts for the Dream Automotive FK8 mods on my build journal.

Feel free to point your customers there if it would be helpful. At their own risk of course

We'll be offering Dream Automotive products very soon, so it's great to see you've been able to utilize a number of their parts towards your solution!

 

[AlphaDigital]

Thank you, I haven't followed as closely as I'd like. Do you know in your data how fast oil temp goes up over a lap? I'd be happy to redo the numbers.

I know others have posted oil temp vs. time as well, I'll look around.(of course it only helps if they have the pace)

Not his data, but in mine, you can see that I start session 3 off with mid 190s for oil temp and 10 minutes in before I have to pit, Ive touched low 270s. This is in 85 degree weather with no oil cooler utilizing 0w20 Motul 300v. Most of this session im only about 6/10ths and maybe 8 or 9/10ths on lap 3 to try and get a decent time.

 

[yargk]

Not his data, but in mine, you can see that I start session 3 off with mid 190s for oil temp and 10 minutes in before I have to pit, Ive touched low 270s. This is in 85 degree weather with no oil cooler utilizing 0w20 Motul 300v. Most of this session im only about 6/10ths and maybe 8 or 9/10ths on lap 3 to try and get a decent time.

Awesome, thanks! I think the gain during the fastest lap is probably the most relevant and it looks like you went from 242 to 257 in 84 seconds. (red gauge in the video on the right, correct?)
This is about 80% of the heating described in my long post, so maybe overheating at a rate of 10 kw or 34000 btu/hr. If you add an oil cooler it would be interesting to see a session on the same track at close to the same temperatures.

Did you have water temp too?

 

[AlphaDigital]

Water temp is the gauge on the left. Oil temp is the gauge on the right.

I should have data to compare after my next track day in september.

Sponsored