The begining of the end of the traditional internal combustion engine???

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Mechanical Moz
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aerobod
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I was at a track day yesterday when one of the participants I know brought along a Tesla Model 3 Performance Edition instead of his usual BMW M4, due to the expected rain through the day. Luckily we got half the day completely dry in the end.

Basically he could only get 2 hot laps of the 2.7km 14-turn circuit before overheating the tyres and brakes and had to then back-off for the rest of the session. He didn't reach limp mode from a battery overheat perspective likely due to the short straights of the course giving limited opportunity for continuous full power. Typically he was covering 40km in about 25 minutes in each session and using 30% of the 75kWh battery capacity, so had to go in search of a DC fast charger off-site after a couple of sessions to be sure that he didn't end up stranded.

The car did handle well with it's low centre of gravity and had reasonable grip, but was otherwise a bit limited for track use. His general conclusion is that it wasn't a good choice due to weight and power consumption.

James

sforshaw
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There's actually a Tesla Model 3 track package available which should fix all those problems excepting the range issue: https://shop.tesla.com/product/model-3-track-package For the foreseeable future range and charging for track use are going to remain a problem, although given time we'll mostly likely see DC charging local to most circuits as the network expands ... there's currently more EV charge points in the UK than there are petrol/diesel pumps but not enough superchargers away from the motorway network.

I've done 5000 miles in my Model 3 since taking delivery in late April and quite honestly with the power available (~450bhp) it's no surprise it'll eat tyres on track ... I'm pretty sure it'd leave my SLR for dead in a 1/4 mile dash and it does it effortlessly with the 4 wheel drive. Full torque is available as soon as the motors are turning which if driving quickly in Sport mode actually makes it difficult to drive it slowly, I've not been on track (yet!) but I think at my skill level I'd be doing it in Chill mode rather than Sport just to deaden things down a little, it'd probably be more fun as well!

With regard to charging, if there's a Supercharger local it's not an issue, without one though you'd be in trouble if you didn't keep an eye on things! Even so I'm a complete EV convert and our second car will likely be another EV when we change it, for me ICE's are now for classics and toys :)

Stu.

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aerobod
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I think the track package would allow a few more hot laps, but then reduced power output due to battery overheating would ensue. Probably 5 laps of our local track before reduced performance, with a typical session being 15 laps.

One of the track day members has experience of both the Taycan and Model S with upgraded tyres and brakes on track, saying that the Taycan is definitely able to handle track use over it's full charge capacity, but the Tesla will go into reduced power mode. It seems to be a limitation of the battery cooling capabilities inherent in the design that software tweaking can't solve, even with the Track Package software changes to over-clock the cooling. Also, once reduced power mode is invoked, it can take a while for the heat to dissipate enough to get back to normal power output.

Range anxiety isn't just an electric thing, though, we did have a 911 driver halt our 4th session yesterday due to running out of fuel on track, he definitely got quite a ribbing over that from a socially distanced crowd.

James

sforshaw
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I'm led to believe the Taycan doesn't use regenerative braking to the extent of the Tesla which may make a difference with the battery heat issue.

Stu.

Lotus Seven Club AR Working Group

The register for all numbered limited-edition Caterhams ....... www.thecaterhamregister.net ...... www.instagram.com/thecaterhamregister

aerobod
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Yes, the Taycan has a different strategy being described to me as almost no regen on track, depending on mode. I just found an interesting article that says the Model 3 Performance is capable of 3 to 4 hard laps at Lime Rock (1.5 mile per lap) before reduced power mode, which is better than the Model S P100D could achieve: https://insideevs.com/news/339220/tesla-model-3-battery-can-transfer-twice-the-heat-of-model-s-p100d/

James

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It basically comes down to there not being an EV on the market that would be suitable for sustained track use of the kind that we would find acceptable, from any manufacturer. But as yet that's not what they're designed for.

Certainly if driving the Model 3 quickly it becomes a battle between driver and car to overcome its' technological traits ... for example braking very firmly into a corner becomes confused when coming off the brakes because the regen braking is still slowing the car down, it senses the corner so still applies regen! It also doesn't like nearby hazards, anything that moves will cause warning alarms to sound. It's turning my driving style into the same as Miss Daisy just to shut the car up.

Stu.

Lotus Seven Club AR Working Group

The register for all numbered limited-edition Caterhams ....... www.thecaterhamregister.net ...... www.instagram.com/thecaterhamregister

Mechanical Moz
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Watching this weeks episode of Vintage Voltage (Landrover Defender) and spy a Westfield in the background.

The Electric Classic Cars Facebook page suggests 400bhp/ton, 30kWh battery pack in the engine bay, Tesla drive unit where the diff was. https://www.facebook.com/electricclassiccars/posts/2420921301565361

I wonder what sort of range they get on track?

 

aerobod
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With a 30kWh battery pack, the car will likely weigh about 750kg, that would indicate a 225kW motor at 400bhp per tonne. If the car averages about 1/3 power level (100% on straights, -40% (regen amount vs heat lost in brakes) under braking and about 40% elsewhere), then 90% of 30kWh would give 22 minutes of run time. On an average track that will be about 40km or 25 miles.

James