MASTER THREAD: Comprehensive Road-Course Modification Guide — Optimizing the 3 for the track

[TwoK4drSi]

Front airflow on oil cooler. It's hot and not cooling down enough. Stock coolant radiator must be increase as well - no doubt about that.
It was 0 regen. I'm certain it helps. Seb made more than 100 laps here comparing it.
It is a jack point yes.

Today we did 7:44 with racenavigator video. I will post later. Still with slight dumb traffic and overheating. Without that it will be below 7:30 and can challenge Taycan lap record.

Unfortunately this season there won't be laptiming allowed. But we will try rework cooling and do faster lap next Saturday. Weather though is unpredictable.

Wow another 11 seconds. Would an electric fan or some type of surface cooling like nitrous or dry ice work? It was done in the Ford Vehicle. Or else you’ll need to cut some holes which maybe isn’t that desirable.

I also think the key is to have a duct / shroud that is direct into the radiator / radiator fan. On the Toyota Supra forums a lot of guys want to remove the fan shroud for the radiator but it overheats. A good flowing fan that pulls/push a lot of cfm like FAL or Mishimoto have solved a lot of cooling problems
Performance Aluminum Fan Shroud Kit, fits Nissan 350Z 2003-2006

See 6:30 of this video

 

[TwoK4drSi]

I watched the video and so between the first Nurburgring run and this run 26 seconds (anticipating 15-20 seconds more) was shaved off by changing to:

UP 10.5 wide wheels, Advan 295 tires, UP CCB brakes, UP 2 way race suspension, UP wing, and UP FUCA, and prototype cooling? If you can figure out the cooling that will be close to a 45 seconds shaved. That’s nuts.

 

[Mash]

I watched the video and so between the first Nurburgring run and this run 26 seconds (anticipating 15-20 seconds more) was shaved off by changing to:

UP 10.5 wide wheels, Advan 295 tires, UP CCB brakes, UP 2 way race suspension, UP wing, and UP FUCA, and prototype cooling? If you can figure out the cooling that will be close to a 45 seconds shaved. That’s nuts.

That's another driver also and less traffic. Also it's not a first lap for Luis on that car. Misha had only 1 and he slowed down much more at speed limits.

And no passenger -80kg.

 

[MountainPass]

Congrats! Car looks awesome. Congrats on the Unplugged sponsorship as well. Glad to see recognition for one of the coolest Model 3's on the ring.

We'll have a to post to answer the oil cooler questions shortly, as you guys know we are trying to collect data and do controlled tests and not make conclusions too quickly until we really understand the results. Regardless it is very promising.

Sasha

 

[Mash]

Congrats! Car looks awesome. Congrats on the Unplugged sponsorship as well. Glad to see recognition for one of the coolest Model 3's on the ring.

We'll have a to post to answer the oil cooler questions shortly, as you guys know we are trying to collect data and do controlled tests and not make conclusions too quickly until we really understand the results. Regardless it is very promising.

Sasha

Thank you, Sasha.

I wouldn't call it sponsorship, its a collaboration. I'm coming close to pay a second car price on mods and r&d. And the whole rear suspension arms setup is MPP on that car, but you didn't sponsored me either. But you've helped me more than few times. I call it collaboration.

 

[MasterC17]

Thank you, Sasha.

I wouldn't call it sponsorship, its a collaboration. I'm coming close to pay a second car price on mods and r&d. And the whole rear suspension arms setup is MPP on that car, but you didn't sponsored me either. But you've helped me more than few times. I call it collaboration.

I know how you feel! Fortunately, we have some great companies to collaborate with! MPP has been an incredible partner to me. VIR may not be the Nürburgring, but my next event on Grand should be a great baseline for what the Model 3 is capable of.

 

[Mash]

Fixed video

 

[bl187]

That's a nice time!!! I am following your progress hope we will see you in the 7:30 territory.. Keep on with your effort I understand the difficulties involved in such an accomplishment.

 

[subieworx]

Had a meeting yesterday with C&R about making coolers for the car. They have a brick cooler that they think will work for the motors and think that it will be the biggest factor for keeping the car cool. Engineering is working on what they need to move forward with the project.

C&R was the company that did all of the coolers for that Ford Mach E race car from a few posts up so they definitely know what they are doing. They just hadn't considered the Tesla as a viable market until I brought it to them.

 

[Mash]

Had a meeting yesterday with C&R about making coolers for the car. They have a brick cooler that they think will work for the motors and think that it will be the biggest factor for keeping the car cool. Engineering is working on what they need to move forward with the project.

C&R was the company that did all of the coolers for that Ford Mach E race car from a few posts up so they definitely know what they are doing. They just hadn't considered the Tesla as a viable market until I brought it to them.

Not necessarily they know what to do with Tesla. They might just make a radiator and be done with it. And what are you going to do with it? They do drop-in replacement. What are you going to replace? How are you going to warm up battery cells to fast charge?

 

[subieworx]

Testing testing testing. That is the only way to know for sure which mods will help in which ways. There will be some failures, but that is better than not trying at all.

The Tesla's system is smart enough to close off the front air dam to the coolers when the system is too cold. For the purposes of charging the battery if the air dam is closed off air flow will drop dramatically to the heat exchangers which will reduced the effectiveness of the cooler bricks on the motors effectively bringing up the overall temp of the system. The system can also ramp up and down the water pumps as needed to control the flow of coolant and hence the overall temperature of the systems.

We are working on creating more cooling capacity for track use first and foremost. That means getting the heat out of the motors more efficiently than the current cooling bricks as a starting point. Once that is done we will move on to a more efficient heat exchanger on the front of the car. We are also looking at more efficient AC condenser.

 

[Mash]

The shutter box is closing to decrease aero drag only.
Tesla is using a 5-way valve to send coolant bypassing the radiator.
But if you want to cool down oil - that's another story.
I still don't understand what you call a "brick".
Also, not sure which one of the 3 heat exchangers you're talking about.

 

[subieworx]

There are three cooling bricks for the drivetrain. One on each motor and one off the 5way valve.

 

[Mash]

There are three cooling bricks for the drivetrain. One on each motor and one off the 5way valve.

I see, so you call heat exchangers "bricks" and what will be "heat exchanger" then - radiator or condenser?

If they can actually make much higher power heat exchangers so that they fit into stock locations - that would be great.

 

[subieworx]

There are a total of 5 heat exchangers in the cooling system on a dual motor car. One on each motor, one on the 5 way valve, a condenser for the AC and a radiator in front of it.

The low hanging fruit would be to design a better heat exchanger (brick) for the motor to help carry the head away more efficiently for it to be shed by the front mounted heat exchangers.

 

[Mash]

I agree but you also need much larger radiator - it's small and it's already overloaded. And if you pass hot coolant through the exchanger - it's no use

 

[TwoK4drSi]

I agree but you also need much larger radiator - it's small and it's already overloaded. And if you pass hot coolant through the exchanger - it's no use

Would a vented hood let more air in and the front tub / front under panel removed (I am already assuming you are doing this)

Also when are you planning on going back out?

 

[MountainPass]

The reason we've elected to go with an oil cooler rather than larger heat exchangers is due to the reason that unlike an internal combustion engine, there are two systems on the Model 3 with slightly different operating temperatures. The battery really needs inlet coolant temperature in the 25-30C range, and the Drive Unit can accept inlet temps in the 35-50C range.

Tesla already has a method of keeping the two systems separate - when the AC Compressor is running and the system is in Parallel mode, the AC Compressor can focus on removing heat out of the battery.

The oil is the hottest fluid, so using an oil cooler with fans allows a direct interface with the hottest fluid to the air. It is also the simplest to install. Any heat that is removed from the oil cooler is heat that is not going into the heat exchanger - so that means cooler loop temperatures and reduced temperature into the battery when the system goes into series mode.

The fan can also be independently controlled, so to Mash's point if you are concerned with heating the battery quickly for supercharging, not running the fan will result in simply a little bit more thermal mass in the oil system, but not a significant delay in heating the system (this is something I know for sure as we tested supercharging and there was no issue for the battery loop to get up to temperature for supercharging).

So all in all, pulling out a ton of heat with oil coolers seems like the logical way to go.

Beyond that certainly, a more hardcore approach would be a larger AC condenser, chiller, and radiator.

However since the system is so complex, and Tesla has multiple different ways of doing the control systems, it's harder to make a perfect back to back comparison. What I can say is that when we disconnected the AC Compressor from our RWD car, without the oil cooler the drive unit overheated in 2 laps. With the oil cooler it didn't overheat for over 15 minutes.

You can put your hand behind the fan and feel the amount of heat coming out of that thing when the Oil Temperature is 70 degrees C!

Here's an overlay from some road testing we did on our LR RWD. The testing consisted of full-throttle power pulses from 60-110km/h. The stator temperature is down 8degC, the oil temp is down 2degC - but the big difference is that the powertrain and battery loops are down 2.4 and 1.3degC respectively - because the oil cooler is working in parallel with the existing heat exchanger. You can also see the significantly different slope of the rear oil temperature.

The colored traces are without the oil cooler, and the white traces are with the oil cooler.

 

[MasterC17]

Would a vented hood let more air in and the front tub / front under panel removed (I am already assuming you are doing this)
View attachment 608296

Also when are you planning on going back out?

Without ducting the air that passes through the box directly out of the hood I don't think it would make any difference at all. That would be impossible using the stock radiator/condenser box as the air is currently being directed out of the bottom of the car (so opposite direction).

 

[Mash]

Did you put actual oil temp sensors or it's still the same wrong CAN data?

I completely agree that oil is hottest and should be cooled down. But heat exchanger does just that as well and liquid-liquid heat exchangers being done right are very effective. At the same time for the front radiator we have large airflow. And radiator obviously can be much larger. Even 2021 version might be enough.

Btw, it makes a lot of sense for me to make some heat wrapping on AC heat exchanger - it soaks heat for no good reason at all and it gets wet since it's cold.