It was 4:08ᴀᴍ. As my body tends to do before leaving for the track, I was awoken a few minutes before my alarm. I always wonder if this is because of an amazingly accurate internal clock or if the anxiety of oversleeping diminishes the quality of my shuteye. In any case it was time to head out the door.
I started Emotive Engineering with a dream, a vision, and having never turned a single lap at the race track in an Electric Vehicle. After being left in the dust out of Turn 11 at Laguna Seca by a Model 3 Performance, I knew full well that this was the future. I also wanted to commit to making gradual modifications to the car to understand the platform and the effect of individual changes. The mantra for Project Emotiv3 is "in the name of science".
So with science in mind, learning and feedback was the name of the game for the first track day out in Emotive Engineering's 2022 Model 3 Performance. The car left my house with about 100 miles on the odometer. It had been driven from the Tesla Store in Colma directly back to the shop, with the only other drive being a quick Skyline Run to the coast to get a feel for the car.
This is incorrect. Vast majority of vehicle motion is returned to the battery, as the electric motors act like a generator in reverse. Brake pads on a Tesla literally never need to be replaced for lifetime of the car.— Elon Musk (@elonmusk) December 26, 2018
While it would be fun to say I took the car to the track with all stock everything in the name of science, I don't have a death wish. Elon Musk has famously claimed that the brakes on Tesla's never need to be serviced, but I can assure you he did not say this with track use in mind. The car has no aftermarket parts, but I took the time to switch out the stock DOT3 brake fluid over to Motul DOT4 RBF600. The internet forums show many recommendations for higher boiling point fluids such as Castrol SRF or Motul RBF660, but a shelf full of RBF600 and a mind towards experimentation pushed me in the direction of the more economical fluid.
I was also partially comforted by the fact that I would be running the OEM 235/35R20 Pirelli PZ4 tires in T0 ELECT specifications. These are not a sticky race tire and I assumed the lack of outright grip would be somewhat easier on the brakes.
The first mistake I made was not plugging the car in early enough to leave the house with a completely full charge. While the car's state-of-charge percentage was in the 90s, this meant that every percent I did not have would be extra time spent before the event at the Supercharger. Speaking of Superchargers, I was headed towards Thunderhill Raceway in Willows, CA. Willows, CA is smack dab in the middle of the 55-mile gap between the Williams Supercharger to the South and the Corning Supercharger to the North. I arrived at the Williams Supercharger at about 6:30ᴀᴍ with less than 20% of charge and a mandatory 7:45ᴀᴍ driver's meeting looming above my head.
If you know anything about Tesla Supercharging, you will know that navigating to the Supercharger to help the battery pre-condition and showing up with a lower charge is the best recipe for fast charging. Unfortunately, this fast charging gets you quickly to 80% and crawls towards 100% as the on-board charging controller reduces the charge rate in order to protect the battery. There was no way I was going to get a full charge and make the driver's meeting so I watched the Waze estimate to the track like a hawk trying to squeeze out every last watt of charge.
I showed up at the track on time for the driver's meeting and immediately plugged in to an RV outlet alongside the track wall at Thunderhill's Turn 1. The RV outlet takes a standard 14-50 plug for which an adapter is available directly from Tesla for $45. This provides a maximum charge of about 30 miles an hour. This was a huge help to top off, but I knew that the power consumption on track would be high and this was only a helpful bandaid. By the time first session came up the car was only at a 65% state of charge (SOC). I knew I would not be getting full power and that I would either need to wake up earlier the next time I came to Thunderhill, tow the car up on the race trailer, or figure out how to use non-Tesla charging infrastructure available at the freeway exit for the track.
Photo: Trevor Ryan
With the daylight slowly rolling in, the end of the first session went smoothly. Before I went out on track I had set the tire pressures across the board to 32psi. Using the voice recorder on my phone I went about checking pressures at each corner but the day was too windy for me to clearly hear every last reading. I can vaguely make out 39.5psi hot which is less than the factory recommended 42psi cold pressures which were designed for efficiency. I thought this seemed like an alright pressure especially as the tire wear looked relatively evenly distributed and that warmer temperatures later in the day would bring this up.
My session best time was a rather slow 2:22.54 as measured by my Apex Pro Track Coach. As a racing driver this is where I insert all of my excuses. This was my first time on track with this car on stock tires and stock brakes, both of which were not very confidence inspiring. The Pirelli PZ4 are a 280 treadwear tire meant for efficiency and Tesla's CEO himself said that the brakes are barely meant to be used. On top of that, I was not getting anywhere near the full power out of the car at the levels of charge the battery was at. As I made excuses in my head, there was still one critical problem: math.
My SOC had dropped to 39% after the first session which meant I had used up 26% not pushing the car at 100% and I had a 34 mile trip back to the Williams Supercharger to power up. Even if I trickle charged from the 14-50 I would be sweating bullets and miss one of the 3 pre-lunch track sessions. Angry at myself for not baking in more time to the schedule, I reluctantly decided to skip the second session and head out to charge so I could be back for the third. Hopefully the long lunch break meant I could trickle my way up to a decent charge to track with and repeat the charging loop.
Photo: Trevor Ryan
I returned in time for Session 3 with a healthier charge level and much more comfort with the car. I was pitching it deeper in to turns that I knew I had taken more cautiously, such as Thunderhill East's tricky off-camber Turn 3 where I have spun other cars before. The car felt balanced, almost as if I was driving a mid-engined Porsche Cayman. That heavy battery weight placed low and in the middle of the Tesla allowed me to comfortably rotate the car at the limits of the designed-for-EV Pirelli tire's grip. I finished the session with a 2:17.33 which I was quite happy with. If I could knock off 5 seconds every session I would hit the sub-2 minute mark in no time.
Photo: Trevor Ryan
Unfortunately that next session mark wasn't meant to be. A car in the previous run group found its way deep off track which shut the track down for quite a while. Thankfully the driver was safe, but the track workers needed to figure out how to get enough tow rope to pull the car out of the mud outside of Turn 6. By the time the track was cleared there wasn't enough time for a full timed lap.
Over the course of the next few months we will be slowly modifying the car in the name of science. The first modification is not a modification at all. Given the distance between the track and Tesla's Superchargers, trickle charging from the RV outlets while Supercharging at lunch is an exercise in frustration and futility. If I had the, now discontinued, Tesla CHAdeMO adapter I would be able to charge at the freeway exit for the track about 10 minutes down the road. The CHAdeMO seems to be a must have specifically for Thunderhill.
The next significant modification will be upgraded brake pads. Having used G-Loc Brake Pads on my track-prepped Miata as well as my Spec Corvette racecar, I am a huge fan of their bite and modulation. G-Loc also happens to be one of the few brake pad manufacturers that have applications for the unique shape of the Model 3 Performance front and rear rotors. A set of G-Loc R12 race compound pads in front and R10 compound pads in rear will be the only modification to the car we make before we hit the track again.
Overall, despite the newbie track EV charging mistakes I would consider the day a great success. The car is a well-balanced platform and I am looking very forward to learning about this chassis and developing the car in to a very capable track weapon. A huge thanks go to Corsa Club for hosting the day and to Trevor Ryan for the amazing on track shots. Happy motoring!