Model 3 auto-x questions

[Dolemite]

A few questions for you guys who are actively autocrossing your TM3s...

1. How many runs do you typically get in for an entire day? I know "it depends" on the organization, number of people, etc. I haven't been in years, and it used to be borderline not worth it vaporizing an entire Saturday to drive for <5 minutes total, which leads me to...
   
   
2. Any venues you've seen with a 240V outlet? Would be awesome to plug in, charge, and watch movies in air conditioning while waiting for your run vs. standing on the sweltering pavement talking to some guy about how nobody wants to race his purple Miata anymore because he's "too fast"
   
   
3. If no nearby charging, what's your charging "strategy?" Arrive with as much as possible?
   
   
4. How much % does each run consume? I imagine the range in answers here is much "tighter" than a road course
   
   
5. Is there a noticeable increase in times as power goes down?
   
   
6. What types & sizes of tires are you running & how long do they last?
   
   
7. Any need to worry about brakes for auto-x? P3D-

 

[SK360]

We typically get 5/6 runs depending on the turnout and our venue is small so typically 30-45 second courses.

No outlets where we run since it’s a swimming pool parking lot in a county park... however the other local AutoX club runs at our local road course in their vehicle dynamics area and they have a clippercreek level 2 charger on site.

There’s a supercharger 10 minutes away at a Sheetz gas station so I’ll stop and charge to 90% and grab breakfast.

It seems to typically be 2-3% per run depending on course... if you check my YouTube videos I have state of charge in the corner (second half of this video), I have a bunch posted

You’d have to be pretty low SoC to notice at AutoX

255/40/18 Bridgestone RE71R.... which are discontinued now so not sure what my next tire is. Plus I want to go wider since I’m not stock anymore. I have 11 events on them (plus driving there and back) and will probably be good for another 3. But it depends on the surface and your driving style.

My buddy runs a LR AWD and at another local venue that is very high speed he has trouble overheating his stock brakes.

 

[SK360]

Here’s a run from the other local venue I mentioned.

And here’s what my RE71R’s look like now. Now that I will have front camber it should help them wear better

 

[Dolemite]

Here’s a run from the other local venue I mentioned.

And here’s what my RE71R’s look like now. Now that I will have front camber it should help them wear better

View attachment 633177 View attachment 633178

That was gonna be my next question - whether you felt front camber was necessary. Thanks for the input.

 

[MODEL+]

I plan to run mine this coming auto-x season, I will take some notes while I'm out there

 

[superflyrolla]

I usually get 6-10 runs. Totally depends on the number of people, number of cars that can safely run at the same time, number of timing problems, and often the number of ICE cars that break down and take 30 minutes each to clean up after. We have an oval track where we can get 1:30 runs using the inner and outer oval. Other venues are 30-40 seconds. IMO, autocross is certainly not worth it for the driving time. It's fun to make friends, have friendly competition, and it doesn't require destroying the daily drivability of our cars.

A few venues have 120V outlets. Right or wrong, I've found it's easier to plug in and ask for forgiveness later rather than trying to seek permission to use them because there's no one to ask. The group is paying to use each venue including bathrooms, parking, electricity right? The best strategy is to show up fully charged. If there's a supercharger nearby, I'll stop there for breakfast beforehand. If no supercharger, I've started racing at 70% SOC. Not ideal, but still fun.

Average run eats 2-3% battery. If anything my times get faster as I learn the course. I think that my times only get slower if my tires get too warm or I aggressively overdrive the car. Blaming the state of charge would be a great excuse, but I do not think that's a big factor.

I've run the MXM4s, PS4S, and RE71Rs at autocross on the Model 3 LR nonP. They're all fun. Coming from autocrossing WRXs, I think starting on less sticky tires may have taught me to drive the Model 3 better. It's easy to overdrive the car and sticky tires cover up my mistakes. The RE71Rs usually get me top 3 PAX (Super street in a nonP) and I can drive on them to the events. I'm impressed. I've probably done 10 events on these tires. I'll flip them on the rim for next season and hope to get another 10. I imagine the lack of track mode is allowing me to get more life than you guys.

I think the brakes stink, or the car is just heavy. My rotors have turned funny colors and I've bled the brakes to make sure I don't have boiled fluid, but I've never replaced pads or anything after doing this for 2 years.

 

[RC10M3P]

I charge to 100% before leaving in the morning and there is a SC station near the venue and I'll try to top off and ensure I have at least 80% SOC, and will use around 3% per lap and get 6-10 laps and don't notice any decrease in power.

I've gone completely stock in my 2021 and and the 235 P-zeros did better than expected although laterally and braking were certainly more limited. Stock brakes also were fine as you don't generate enough heat between runs to cause any deterioration in feel and stopping.

See video from my fully stock 2021 below. I have new TSW Bathurst wheels and 265/35/19 RT-660s coming for my next event, along with a front anti-roll bar.

 

[MODEL+]

I charge to 100% before leaving in the morning and there is a SC station near the venue and I'll try to top off and ensure I have at least 80% SOC, and will use around 3% per lap and get 6-10 laps and don't notice any decrease in power.

I've gone completely stock in my 2021 and and the 235 P-zeros did better than expected although laterally and braking were certainly more limited. Stock brakes also were fine as you don't generate enough heat between runs to cause any deterioration in feel and stopping.

See video from my fully stock 2021 below. I have new TSW Bathurst wheels and 265/35/19 RT-660s coming for my next event, along with a front anti-roll bar.

Awesome driving and insight! that coarse layout also looks like a lot of fun!

 

[RC10M3P]

Awesome driving and insight! that coarse layout also looks like a lot of fun!

Thanks!

I also forgot to mention that a water sprayer is really necessary to keep tire temps under control, especially since the model 3 is quite heavy and under tire'd.

 

[Dolemite]

Thanks!

I also forgot to mention that a water sprayer is really necessary to keep tire temps under control, especially since the model 3 is quite heavy and under tire'd.

Definitely under-tire'd. I'm DDing 265/35 19s over summer & I'll probably auto-x w/ the same if I "get back into it." Hoping they'll be OK.

 

[Mash]

It has not enough tires even for the weight, hence high stock pressure. It's certainly not enough for power.

 

[RC10M3P]

So I did encounter in my last autocross where I had 12 runs plus 2 re-runs, that the power did noticeably decrease below 50% SOC. I started the event at 92% SOC and my acceleration and lap times were pretty good until I dropped below the 50% and then my acceleration curves were notably flatter than the runs from earlier in the day. The course was very high speed though, hitting around 70mph and ~53-55 seconds long. See video of course below from one of my quicker runs.

 

[RC10M3P]

The red line is from one of my last runs, and as you can see I carried more speed through the corner, but the slope of my speed increase (the acceleration), is flatter than the other runs.

Unfortunately my OEM tesla usb did not come with a track mode folder so I can't also confirm it with power data, but I think it is safe to assume to try and stay between 55-90% SOC for most consistent power.

 

[MODEL+]

So I did encounter in my last autocross where I had 12 runs plus 2 re-runs, that the power did noticeably decrease below 50% SOC. I started the event at 92% SOC and my acceleration and lap times were pretty good until I dropped below the 50% and then my acceleration curves were notably flatter than the runs from earlier in the day. The course was very high speed though, hitting around 70mph and ~53-55 seconds long. See video of course below from one of my quicker runs.

Looks like so much fun! I wished my local autocross here in Portland allowed me to hit up the 70mph...
I'd be lucky if I could clock in 45-55mph...

 

[RC10M3P]

Looks like so much fun! I wished my local autocross here in Portland allowed me to hit up the 70mph...
I'd be lucky if I could clock in 45-55mph...

Yeah, PIR doesn't have a lot of space to hit those speeds. Packwood would certainly have a better chance.

 

[MODEL+]

Yeah, PIR doesn't have a lot of space to hit those speeds. Packwood would certainly have a better chance.

You're familiar with the events up here in PNW?

 

[RC10M3P]

Yeah, I used to live near Portland. I have a few friends that still run there regualarly.

 

[Dallas J]

Yep, Packwood is the place to be if you want more speed or make the trip down to Crows.

 

[Let's Drive]

A few questions for you guys who are actively autocrossing your TM3s...

1. How many runs do you typically get in for an entire day? I know "it depends" on the organization, number of people, etc. I haven't been in years, and it used to be borderline not worth it vaporizing an entire Saturday to drive for <5 minutes total, which leads me to...
   
   
2. Any venues you've seen with a 240V outlet? Would be awesome to plug in, charge, and watch movies in air conditioning while waiting for your run vs. standing on the sweltering pavement talking to some guy about how nobody wants to race his purple Miata anymore because he's "too fast"
   
   
3. If no nearby charging, what's your charging "strategy?" Arrive with as much as possible?
   
   
4. How much % does each run consume? I imagine the range in answers here is much "tighter" than a road course
   
   
5. Is there a noticeable increase in times as power goes down?
   
   
6. What types & sizes of tires are you running & how long do they last?
   
   
7. Any need to worry about brakes for auto-x? P3D-

1. About 6 runs per session, depending on format and number of people. I usually do AM sessions, though.

2. It really depends where we're running. At Summit Point they have paid charging, while at most of the stadiums/lots, no.

3. I pretty much arrive with as much as possible, after leaving home with as close to 100% as possible and topping off at a supercharger, if necessary.

4. It depends on the course, but about 2%+. I've attached an image after one of my runs, but it gets averaged out quickly.

5. For me, no. Since the courses are more technical and less outright speed, I've found power doesn't really make a difference, especially since you're only losing a few percentage from what you arrived with. More experience and time on the course as a driver is the much bigger factor, IME.

6. I drive strictly for fun, and my sessions were done 100% stock, 20s and all. The guys who are more dedicated drop to 18s and go as wide as possible, so I can't really say. I'm still not on a dedicated setup, but this year I'll be on something wider/lighter.

7. In my experience, not really (if you're talking about heat concerns). The runs are too short and there's a good bit of time between runs. (Regen helps, but this is one area where I think regen on the brake pedal would be better).

Also, I usually see a few other Model 3 drivers when I go out, which is nice, since you can chat and compare experiences. The 3 is heavy, but a fun car to autox, even in the wet.

 

[MODEL+]

Got her First Autocross in last Sunday.

It was a different experience doing it with this car but a pleasurable one. Took some notes and did a little write up on our thread:

Vendor - TMC's Premier Aftermarket Support | Wheels, Suspension, Styling Parts, & More | MODEL+

Hello TMC Community, My name is Danny, director, and founder of MODEL+ MODEL+ is a boutique style shopping experience solely catering to Tesla Model 3 and Model Y platforms. By this approach, we are able to curate and offer only the best parts available at various price levels. As a consumer...

teslamotorsclub.com

Enjoy,
Danny