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Dominion Raceway Road Course Fast Laps

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To a large degree it is. The S would basically go into limp mode and you wouldn't even be able to stay out on track. The 3 results in ~7-10% slower laps. So, not a huge difference, but still annoying.
It's not that different from high power road cars - they overheat. Oil temps, coolant, brakes. Model 3 has tiny cooler and plenty of space for modding something better. Just need to sacrifice frunk that you don't have anyway with ICE (or no trunk).
 
It's not that different from high power road cars - they overheat. Oil temps, coolant, brakes. Model 3 has tiny cooler and plenty of space for modding something better. Just need to sacrifice frunk that you don't have anyway with ICE (or no trunk).

;)

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Cool! Details, please. How are you going to extract hot air? I was thinking installing additional radiator on top of the box, but I didn't dig inside to see how the box is even constructed, so I'm blind guessing.

UPP might design new bumper that goes back to where all ICE cars now - front mount radiator. Enough of this BS that electric doesn't have combustion motor, so no heat and no radiator grill. Yes, it wastes MUCH less energy into heat, but it's still not good enough for the track abuse.

I would probably fab a new radiator box from aluminum sheets and still use existing active grill, but did better air routing to the windshield. I have a feeling there is enough of air opening already, just need to have more radiator area and lower air resistance through radiator.
 
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Cool! Details, please. How are you going to extract hot air? I was thinking installing additional radiator on top of the box, but I didn't dig inside to see how the box is even constructed, so I'm blind guessing.

UPP might design new bumper that goes back to where all ICE cars now - front mount radiator. Enough of this BS that electric doesn't have combustion motor, so no heat and no radiator grill. Yes, it wastes MUCH less energy into heat, but it's still not good enough for the track abuse.

I would probably fab a new radiator box from aluminum sheets and still use existing active grill, but did better air routing to the windshield. I have a feeling there is enough of air opening already, just need to have more radiator area and lower air resistance through radiator.

This is really more proof-of-concept than anything else. I would wait for a legit solution from MPP assuming this actually does anything (fingers crossed).

Air is extracted the same way as stock. Basically, this radiator is much taller (about the same size as the condenser, which is 3x that of the stock radiator). It's also much thicker (about 2-2.5x). So, I put it in the same location as the stock radiator, but opened the stock "box" at the top enough to slide the radiator down into it and not hit the louvres. To fill the gaps, I used automotive insulating foam (stick-on) and 3M Aluminum Tape. So the amount of air coming in and going out is the same, but the volume of air going through the radiator and the capacity of the radiator is much higher. I was considering drilling two 2-3" holes in the stock front bumper, running them under the impact beam, and then into the stock louvre shroud for additional air flow IF it appears that, that would be needed. If you use a hole-saw you can save the old pieces of the bumper and bolt them back in when not tracking the car so it looks less tacky (same thing I did with the brake ducts on the aero shield).

I completely agree about the whole "EV's don't need grilles" thing, honestly I think most people don't even know that EV's have "engine oil" and "radiator coolant" in them, just like every other car.....lol
 
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Wow, thanks a lot. Mesh is a question - it will stop garbage, but it also loses pressure significantly at high speed.

About radiator, I got it. I have a feeling that it makes sense to remove radiator from condenser and put it horizontally on top of the box. Since it's large it can work with just a static pressure of air. But that allows to give more cool air to condenser. Considering that they already running compressor on overdrive, I believe it's way more important to cool down condenser, so less restrictions at input and output and no front heaters.

Condenser is hotter and therefore better heat exchanger than radiator.

Another problem, though, that top opening going to lose static pressure, so flow through condenser might drop. Anyway, keep us informed - it's very worthy project.I t's great MPP is working on that. I am a supporter of stock look, so I hope we won't need bumper drilling :)
 
Wow, thanks a lot. Mesh is a question - it will stop garbage, but it also loses pressure significantly at high speed.

About radiator, I got it. I have a feeling that it makes sense to remove radiator from condenser and put it horizontally on top of the box. Since it's large it can work with just a static pressure of air. But that allows to give more cool air to condenser. Considering that they already running compressor on overdrive, I believe it's way more important to cool down condenser, so less restrictions at input and output and no front heaters.

Condenser is hotter and therefore better heat exchanger than radiator.

Another problem, though, that top opening going to lose static pressure, so flow through condenser might drop. Anyway, keep us informed - it's very worthy project.I t's great MPP is working on that. I am a supporter of stock look, so I hope we won't need bumper drilling :)

You would definitely need another source of air if you were running the radiator out of the box. I didn't want to jump to drilling holes, so that's why I started in the box.

It's also worth noting how the cooling system works. The radiator is primarily for drive unit/powertrain cooling, and the A/C condenser and chiller are primarily used for battery cooling. Depending on what you are trying to accomplish, you would either run them in series (heat transfer) or parallel (decoupled).

For example, if you are pre-conditioning for Supercharging you would run them in series as the waste heat from the drive unit will cause the battery temperature to increase more quickly.

If you are cooling the drive units you would also want to run in series as the battery coolant is going to be much cooler than the drive unit coolant.

However, if you are ONLY trying to cool the battery and not the drive units, you would run them in parallel (decoupled).

Unfortunately, I don't actually know exactly how the car behaves in Track Mode, and I assume it changes depending on what is hot and when. What I have noticed that I find odd is the absolute battery temperature seems to have nothing to do with the little graphic showing it in red. When Supercharging, temps of 130f are typical. Sometimes the battery will go red at 108f, and other times at 120f while in Track Mode.

My general consensus is that if the drive unit cooling capacity is higher and more efficient, this should (in theory) help keep the battery temperatures more stable by keeping the car in parallel. If you go into series while on track with hot drive units to cool the powertrain your battery temps are going to increase.
 
I'm somewhat lost in your explanation :)

Inside the box there are condenser and radiator. One pushing heat from heat exchanger, another one directly from the coolant lines. My understanding that radiator is afterthought and would not be necessary if heat exchanger is powerful enough. But it's not, so they added radiator.

Now if that is true - you want to cool them both better. Hacking condenser is useless - it's made for heat exchanger power. But you still want to give it more cold air. So radiator in front is not helping with that. Hence my proposal to move radiator on a top part of the box with its own fans assembly - colder input air, lower resistance in front of it.

Radiator also - the colder the better except it wants to warm up. But you have stock active shutter and stock signal for fans power, so Tesla can limit air input and you know when you need to run your fans.

So I'm really confused about series installation. What am I missing?
 
I'm somewhat lost in your explanation :)

Inside the box there are condenser and radiator. One pushing heat from heat exchanger, another one directly from the coolant lines. My understanding that radiator is afterthought and would not be necessary if heat exchanger is powerful enough. But it's not, so they added radiator.

Now if that is true - you want to cool them both better. Hacking condenser is useless - it's made for heat exchanger power. But you still want to give it more cold air. So radiator in front is not helping with that. Hence my proposal to move radiator on a top part of the box with its own fans assembly - colder input air, lower resistance in front of it.

Radiator also - the colder the better except it wants to warm up. But you have stock active shutter and stock signal for fans power, so Tesla can limit air input and you know when you need to run your fans.

So I'm really confused about series installation. What am I missing?

I think your understanding is not entirely accurate. If you removed the radiator there would be nothing cooling the powertrain loop (drive units and power conversion system) when in parallel and the drive units are always going to be much hotter than the battery on track (so always in parallel). The system will only run in series (one big loop) until the drive unit temp starts to exceed the battery temp (which again, on-track is going to happen very quickly) or until it needs to cool the powertrain. The powertrain loop is huge, it goes throughout the entire car basically. So, the radiator is needed as the drive unit operating temperature during hard driving is much higher than that of the battery. I guess if you had a ridiculously effective heat exchanger that could keep the battery and the powertrain at 100f at all times you would not need the radiator, but I don't think we are anywhere near that. I agree that you ultimately want to be cooling both of them as effectively as possible.

Again, the behavior I've noticed is it seems like when the car "shows" it is limiting power due to a hot battery, it is actually a result of the car needing to cool the drive units off (as the absolute temperature at which the battery is showing it is overheating varies wildly) and the car is doing this by switching to series which introduces a ton of hot coolant into the battery loop. My theory is that by keeping the drive units cooler, we will be able to keep the system running in parallel, which means it won't need to switch to series to cool the powertrain loop, and then we can let the battery temp increase to its true limit.

This is all hypothetical though, so I really won't know until I can test it in 2 weeks. Your idea of having the radiator outside of the box with fans is definitely interesting and would probably work well, I guess my only hesitation would be that now you have to manually control turning the fans on and off which is a little much for a street driven car. Keeping the stock architecture is important to me IF we can find a good solution.

There is another option - venting air from the existing fog light holes. This wouldn't make the bumper look silly and could push a huge amount of air through the existing box. Perhaps that will be my next step if this does not work.
 
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As a follow up, I looked through the SMT logs and it confirms my thought process. The car starts in Parallel to cool both the battery and the drive units; but after about ~5 minutes on track it switches to Series to try and cool down the drive units as they are heating up MUCH faster than the battery. Ultimately, this causes the battery temperature to heat up. The car switches back to Parallel in less than 3 minutes of being in Series to keep the battery in a good temperature range, but now the drive units are heating up much faster. The Coolant Temp Inlet drops drastically after it switches back to Parallel but the Powertrain Temp Inlet continues to rise quickly. So after about 8 minutes the car is in "oh crap I can't keep up" mode. The drive unit temperature keeps increasing at this point but the coolant temperature stays stable. As we all know, power begins to limit somewhere around the 10 minute mark. What I don't understand is why the Track Mode UI shows the battery in RED when the issue clearly lies in the drive units/powertrain based on the actual data. I looked through several different log sets and they all show the same information regardless of the absolute coolant temperature.

TLDR; The absolute coolant temperature is not the constraint, the drive unit temperature is. A bigger radiator should help this problem as it is the only source of cooling when the thermal system is running in Parallel mode which is will do for the majority of the time while tracking the vehicle.

P.S. - I've also considered using the windshield washer system as a water cooling method. Basically, you would disconnect the two lines that go to the wiper blades and disconnect the plug for the wiper motor. Move those lines over to two new lines that are routed to the radiator box and end in a spray nozzle (think like a methanol system on an ICE vehicle). When you press the stalk to run the windshield washers the spray nozzles douse the radiator/condenser with cool water causing evaporation and "pulling" heat out of the system.
 
As a follow up, I looked through the SMT logs and it confirms my thought process. The car starts in Parallel to cool both the battery and the drive units; but after about ~5 minutes on track it switches to Series to try and cool down the drive units as they are heating up MUCH faster than the battery. Ultimately, this causes the battery temperature to heat up. The car switches back to Parallel in less than 3 minutes of being in Series to keep the battery in a good temperature range, but now the drive units are heating up much faster. The Coolant Temp Inlet drops drastically after it switches back to Parallel but the Powertrain Temp Inlet continues to rise quickly. So after about 8 minutes the car is in "oh crap I can't keep up" mode. The drive unit temperature keeps increasing at this point but the coolant temperature stays stable. As we all know, power begins to limit somewhere around the 10 minute mark. What I don't understand is why the Track Mode UI shows the battery in RED when the issue clearly lies in the drive units/powertrain based on the actual data. I looked through several different log sets and they all show the same information regardless of the absolute coolant temperature.

TLDR; The absolute coolant temperature is not the constraint, the drive unit temperature is. A bigger radiator should help this problem as it is the only source of cooling when the thermal system is running in Parallel mode which is will do for the majority of the time while tracking the vehicle.

P.S. - I've also considered using the windshield washer system as a water cooling method. Basically, you would disconnect the two lines that go to the wiper blades and disconnect the plug for the wiper motor. Move those lines over to two new lines that are routed to the radiator box and end in a spray nozzle (think like a methanol system on an ICE vehicle). When you press the stalk to run the windshield washers the spray nozzles douse the radiator/condenser with cool water causing evaporation and "pulling" heat out of the system.

This is really good info. At what battery temp does the loop go from series back to parallel?
 
This is really good info. At what battery temp does the loop go from series back to parallel?

It looks like the change occurs when the Battery Inlet Temp reaches 105f/ the Powertrain Inlet Temp reaches about 116f. From there, the Battery Inlet Temp DROPS and the Powertrain temp INCREASES. Again, this supports the theory that the weak-point is the Powertrain Loop, e.g. the Radiator as everything else is maintaining/dropping the temperature and the Powertrain is increasing.
 
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