Model 3 Potential in Autocross

[Drivesolo]

Ever since the first Model 3 LR specs were released last month I’ve been pondering what potential the Model 3 might have in autocross. I figured comparing it the Model S would be the closest thing for a hypothetical comparison. I took a look at the 2017 SCCA Solo classification and see that the Model S is currently in F Stock (PAX index: 0.804). I believe that’s only for the non-D versions since the model years specified were 2012-2014 and I don’t see any other classifications for the Model S. Assuming that’s for the P85, that’s really good for a RWD car that size considering that BMW M3’s from 2006-2013 are also in F Stock. A very fast class indeed.

Comparing the physical dimensions between the P85 and the 3LR:
Model S P85 / Model 3 LR
Length (in.): 196.0 / 184.8
Width (in.): 77.3 / 72.1
Wheelbase (in.): 116.5 / 113.2

Size wise, the Model 3 has a significant advantage over the Model S on an autocross course. The CG’s should roughly be the same since they’re the same height (56.8 in.). Since they use the same battery layout their weight distribution should roughly be the same also (Model 3 F/R: 48% / 52%).

The P85 has a substantial power advantage over the 3LR:
Motor / 0-60 mph
Model S P85: 416hp / 443 ft-lbs / 4.4 sec
Model 3 LR: 258hp / 318 ft-lbs / 5.1 sec (TBD)

But, the 3LR is 948 lbs lighter:
Model S P85: 4,785 lbs
Model 3 LR: 3,837 lbs

The P85 runs a much wider tire package than the 3LR:
Front / Rear
Model S P85: 245/35-21 / 265/35-21
Model 3 LR: 235/40-19 / 235/40-19

There are more tire options for Model 3 in 19’s and it would be legal to go down to 18’s for even more options.

Would the Model 3 have good potential for autoX? Would it be as quick as the Model S P85? Could it potentially turn better times than the Model S P85? What other attributes should be considered in an autocross stock class comparison?

 

[JeffK]

Ever since the first Model 3 LR specs were released last month I’ve been pondering what potential the Model 3 might have in autocross. I figured comparing it the Model S would be the closest thing for a hypothetical comparison. I took a look at the 2017 SCCA Solo classification and see that the Model S is currently in F Stock (PAX index: 0.804). I believe that’s only for the non-D versions since the model years specified were 2012-2014 and I don’t see any other classifications for the Model S. Assuming that’s for the P85, that’s really good for a RWD car that size considering that BMW M3’s from 2006-2013 are also in F Stock. A very fast class indeed.

Comparing the physical dimensions between the P85 and the 3LR:
Model S P85 / Model 3 LR
Length (in.): 196.0 / 184.8
Width (in.): 77.3 / 72.1
Wheelbase (in.): 116.5 / 113.2

Size wise, the Model 3 has a significant advantage over the Model S on an autocross course. The CG’s should roughly be the same since they’re the same height (56.8 in.). Since they use the same battery layout their weight distribution should roughly be the same also (Model 3 F/R: 48% / 52%).

The P85 has a substantial power advantage over the 3LR:
Motor / 0-60 mph
Model S P85: 416hp / 443 ft-lbs / 4.4 sec
Model 3 LR: 258hp / 318 ft-lbs / 5.1 sec (TBD)

But, the 3LR is 948 lbs lighter:
Model S P85: 4,785 lbs
Model 3 LR: 3,837 lbs

The P85 runs a much wider tire package than the 3LR:
Front / Rear
Model S P85: 245/35-21 / 265/35-21
Model 3 LR: 235/40-19 / 235/40-19

There are more tire options for Model 3 in 19’s and it would be legal to go down to 18’s for even more options.

Would the Model 3 have good potential for autoX? Would it be as quick as the Model S P85? Could it potentially turn better times than the Model S P85? What other attributes should be considered in an autocross stock class comparison?

What if dual motors ends up being two 258 hp motors... wouldn't you want that?

 

[Drivesolo]

What if dual motors ends up being two 258 hp motors... wouldn't you want that?

LOL. Absolutely, but no information exists on the Model 3 LRD yet. This is just a thought exercise.

 

[blef44]

I was planning on giving it a shot just for fun, but without buying new tires there is no hope at being competitive. I am also skeptical about the braking performance. Overall, it's still a fairly large car and is heavy. The instant torque will make it fun though.

 

[xmetal]

I've raced autox quite a lot over the years (with tuned Subaru, Integra and M3) and after getting my first EV one of my main thoughts was, "Holy cow this would be awesome to autox." While heavy, the instant torque and throttle responsiveness, along with low center of gravity of the Model 3 would probably make it quite a lot of fun. I'm not sure it would ever be a class leader due to weight, but it certainly would be a blast to try.

 

[Drivesolo]

I've yet to see a Model S at an autocross event where I can compare its performance to a vehicle & driver combo that I know and/or to my own times in the car I'm in. From my understanding the one thing that is holding the Model S from it's full potential is the stability control or more appropriately the inability to turn it off. Seems that some people had to pull fuses to disable it, but then that would technically take you out of Stock classification. For any Model S owners who've attempted to autoX their cars, please correct me if I'm misunderstanding these details.

 

[Zaphod]

I've yet to see a Model S at an autocross event where I can compare its performance to a vehicle & driver combo that I know and/or to my own times in the car I'm in. From my understanding the one thing that is holding the Model S from it's full potential is the stability control or more appropriately the inability to turn it off. Seems that some people had to pull fuses to disable it, but then that would technically take you out of Stock classification. For any Model S owners who've attempted to autoX their cars, please correct me if I'm misunderstanding these details.

Pretty sure I've seen people who have autox their S. Might want to mosey over to the S forum and do search or start a new thread.

did a quick search and came up with this article from few years ago:
Autocross in a Tesla Model S

 

[Drivesolo]

Pretty sure I've seen people who have autox their S. Might want to mosey over to the S forum and do search or start a new thread.

did a quick search and came up with this article from few years ago:
Autocross in a Tesla Model S

Yes, I've seen videos of the Model S autocross. There's is little in those videos to draw a comparison on it's performance from known values and a lot of unknowns.

Typically in autocross you can gauge a car's performance if you know the setup and the driver's capabilities. It tends to be very helpful by putting an experienced driver in two different vehicles and do a few runs in each on the same course.

 

[DR61]

I agree the M3 will probably be fun to autocross, but lack of LSD and non-defeatable ESP will be a problem for national level competition. I wonder what tire widths can fit on the two wheel options.

 

[shrspeedblade]

I've long wondered how Tesla would look upon it for warranty work- some manufacturers are finicky about timed competition events. Something I've thought would be fun to try, though.

 

[jerjozwik]

even my poop fiat 500e was pulling great times at autoclub speedways autox event years ago. could just be the drivers of the hopped up mustanges and bmw m3s were crap, but i was getting times close to theirs.

 

[3mp_kwh]

I'd put up with more weight, where Tesla has put it, before going to a ~3,400 pound car whose engine was up high, and off the front.

Anyway, Road & Track had what I'd consider a must read about Tesla's default nanny settings:
Climate Change: 2014 Tesla Model S P85D

I think Auto-X is where the traction control program would be most active. My MS experience tells me low speed and sharper steering angles have something to do with it. So, if you can't pull fuses, or if Tesla isn't going to let drivers get more out of the car, you might want a different one. This is relatively simple stuff, compared to AutoPilot, but not where attention is being placed.

 

[Drivesolo]

Thinking that the need to disable the stability control is essential, I scanned through the rules for Street Category in the 2017 rule book and now I'm wonder if it would even be worthwhile to run the Model 3 in anything other than Stock Class, until there is some decent aftermarket support for the Model 3. I'm hoping there will be a way to disable the stability control as an allowed user setting, but I know that's pretty unlikely.

Any guesses on what stock class the Model 3 might turn up in in 2018? I'm gonna say that SCCA will toss it into F Stock along w/ the Model S. Smaller and lighter but less power might balance it out w/ the Model S. I see the possibility of things getting a little weird in the Model 3's classification. What could happen is that they'll assign the Model 3 a class based on the performance of the 3LR and then a 3LR-D will debut in mid to late 2018. It will be classified as the same as the 3LR which could potentially make the 3LR-D the car to have in 2018, until the rules catch up in 2019.

 

[McRat]

IMO:

The M3 should do well with the right tires, especially if you don't order the PUP which I'm guessing is adding ~250lb up high by using power seats, sunroof, and heavier stereo equipment. You cannot legally reduce weight.

One thing that might suck is the lack of a rear LSD. Using brakes as LSD is a minor problem. What happens, is when you go to accelerate out of the corners, if you have too much speed and give too much pedal, it will bog. Electronic brake control is not as rapid as a true LSD, and it feels like the car is sitting still briefly until the electronics let you apply full thrust again in both tires. Once you realize what the problem is, you just have to be a bit gentler as you roll into it out of the corners.

I think a M310 without PUP will kill any version of the Model S in AutoX, and while it might start in FS, they could bump it. We will see.

It's the same problem you have with Stability Control on in ICE cars, it doesn't react quick. Leaving SC on is a sure way to add a second or more.

Within days of receiving my M310, I'll AutoX it. It's the safest way to find out how the car behaves when pushed hard at legal speeds.

 

[McRat]

I've yet to see a Model S at an autocross event where I can compare its performance to a vehicle & driver combo that I know and/or to my own times in the car I'm in. ...

Twice we ran Chevy Volts when a Model S was there. My best time was just a touch over the MS, 0.2s?. But driver skill is the largest variable. The size of the MS did him no favors.

 

[Drivesolo]

Something that occurred to me this morning; depending on what can be displayed on that center display, it could be a very easy and useful when gathering telemetry on video. It may even be possible to have a view out of the windshield of the course while seeing speed, throttle and brake inputs and also seeing (partial) steering wheel inputs, all in one frame. I'm not familiar w/ what's possible w/ the Model S & X displays so I'm just speculating.

Twice we ran Chevy Volts when a Model S was there. My best time was just a touch over the MS, 0.2s?. But driver skill is the largest variable. The size of the MS did him no favors.

Yeah, I hear ya. Knowing what the driver brings to the equation is key in assessing the autocross performance of any car. The layout of a course could be a huge pain for vehicles the size of the Model S. I'm looking forward to seeing what the Model 3 can do.