Performance Model 3 slower than AWD? Autocross results!

[Daniel in SD]

So, I had planned to take my Exocet to autocross this weekend but it was raining and my Exocet has no roof, doors, or fenders so that seemed ill advised. "Ah ha" I said, "I've heard that Tesla's do well at autocross" so I set my charge level to 100% and headed out. Turns out that @AlanSubie4Life had the same idea and brought his "super gifted" Performance Model 3. I was a little bit worried since he has the vaunted "track mode" and I'm stuck with all the electronic nannies trying to slow me down. Not only that, my basically untested, reject motors would be no match for his "highest sigma, double burn-in" motors. My only hope was that his 20" boat anchor wheels, heavy brakes, and fear of hitting cones would slow him down. As you may have already guessed from the thread title, I was victorious! 78.629s vs. 78.941s. It should be noted that he does not yet have the carbon fiber spoiler which might have given him enough of an aero advantage to eke out a victory. He has apparently tried to hide his defeat by having his car listed as the oil burning Mazda RX-8 (which he did do a set of laps with earlier in the day).
http://sdbmwcca.org/autocross/results/2019-01-12

A few thoughts

• This thing is so easy to drive fast. A fair amount of understeer (though that could be due to the stability control) and body roll, but it seemed super precise.
• The stability control wasn't as obtrusive as I had feared. It was definitely slowing me down on corner exits though. Why not have an off switch like BMW?
• You'll pay for the whole tire but you'll only use the edge! Needs camber badly! If you actually want to autocross it regularly you're going to want tires that are symmetrical side to side so they can be flipped left to right. I was running PS4S tires and I used 1/32nd of tread on the edge of the tire even with 8 laps in wet conditions and 4 laps in damp conditions.
• The seats are horrible for spirited driving. Hold on tight!
• I still prefer my Exocet and given how fast the Tesla will burn through tires the Exocet probably uses less oil

 

[skitown]

Damn, that looked like some great driving.

 

[Daniel in SD]

Damn, that looked like some great driving.

Well, I only uploaded my best lap
The people ahead of me are better drivers. I bet with a better driver, better tires (I'm pretty sure every one ahead of me was running RE-71Rs, the stickiest 200TW tire), and stability control defeat the car could have gotten the 2nd fastest time of the day. AWD was probably a big advantage on the damp asphalt. That Subaru in front of me that got the fastest time was heavily modified with super wide tires.

 

[gaswalla]

1273 watt hr/mile! Awesome

 

[Magnets!]

Nice job. Tires look trashed. What tires are they? What is the plastic on the fender....stone protection? Did you activate slip start...would that be helpful at all? Did traction control cut power that you noticed?

I've done that autocross a few times in an M Roadster and M3 years ago. As I recall at least back then, the course was wide open enough to get into 3rd gear, which is a bit more fun for those in heavier more powerful cars.

 

[gilscales]

how do you like the 265 width tires? did you take a huge hit in wh/mi? oh and Yeah it looked like some pretty nice reflexes out there for sure, good job!

 

[AlanSubie4Life]

@Daniel in SD is currently a slightly better driver (does more autocross, is more aggressive - I used to be better in the RX-8!) and I was dodging potholes and cones with my 20” boat anchors. Also he had wider tires, though that may not help, as he said above. Mostly he seems to drive like a maniac now and has mastered countersteering with power application. Those are the improvements I have noticed which I have not yet acquired!

I did all but the last lap with Track Mode. I was pretty stressed about damaging the new car, but:

The car felt better on the laps with Track Mode, but it says something about my level of distraction that I really did not notice that I was not in Track Mode until the end of that last lap. It does make a difference - in retrospect, I found that I just wasn’t able to get the car to turn in well on that last lap (I did not know why at the time, it was just annoying - thought the tires might be shot! ). I actually did not notice that the power was getting cut; what was obvious is that it was plowing more without Track Mode.

With Track Mode on, I heard loud clunking on several occasions when cornering. I was unable to distinguish whether this from application of the brakes or chunks of the stadium parking lot. I think it was probably the brakes but really don’t know.

Overall it was terrifyingly fast, and like no other car I have driven at autocross - much faster than the old Subaru. It really explodes out of those turns. I only target-fixated directly into one cone, at the end of the fastest slalom (which was really more like a straightaway as you can see above), when I must have been doing 70-75. I think all I had to do was turn (why DIDN’T you turn?!? ). But I really convinced myself there was no way to make the turn. That was a fast lap that resulted in a DNF. Not sure it would have been faster than Daniel’s best - maybe if I had cleaned it it would have been. Or maybe not. Always hard to know. (I pulled the car out of grid to check for damage - and Track Mode turned off, so that is why the last lap ended up without Track Mode.)


I’ll be back at some point with some 18” wheels and Rivals or RE-71Rs or something. And then we’ll see how things go! Or I might just drive the Exocet; he needs someone to help pay for his tire costs.

 

[Magnets!]

Nice job. Tires look trashed. What tires are they? What is the plastic on the fender....stone protection? Did you activate slip start...would that be helpful at all? Did traction control cut power that you noticed?

I've done that autocross a few times in an M Roadster and M3 years ago. As I recall at least back then, the course was wide open enough to get into 3rd gear, which is a bit more fun for those in heavier more powerful cars.

 

[AlanSubie4Life]

What is the plastic on the fender....stone protection?

TrakkTape. He borrowed some from me. I had a lot more on my car. I was paranoid. Never used it before. Expensive, but kept the rocker panels from getting blasted with gravel.

Tires look trashed

I’ve seen a lot worse! Just have to make sure they are well inflated on the street, to balance the wear out a bit.

 

[AlanSubie4Life]

1273 watt hr/mile! Awesome

That’s nothing, I had 1444 Wh/mi! Daniel drives very efficiently I guess.

If the motors in my P3D didn’t ACTUALLY receive double the burn-in from the factory, they have now.

 

[AlanSubie4Life]

how do you like the 265 width tires? did you take a huge hit in wh/mi? oh and Yeah it looked like some pretty nice reflexes out there for sure, good job!

He’s averaging something like 350Wh/mi, so...yes. They’re appropriate for his driving style though!

...I should really have combined these responses all into one post...

 

[Lunares]

I'm moving to RE71's after tearing apart my poor 20" Michelins on a singe track day.

Recommend 255/40/18 or 265/35/18?

I'm also trying to decide if I just go full custom for rims or if I go for Enkei PF01 or Tsportline 18's. (Confirmed with Enkei that the RPF01 does not fit the P3D+)

 

[MoreAgain]

Amazing results Daniel and Alan! It was great to see Model 3s representing toward the top of the leader boards!

This was my first time at autocross in my RWD car, and while not nearly as competitive at the two of you, I still found the experience to be tons of fun! My best lap was an 86.3, which put me toward the middle of the pack overall and a good 8 seconds back from the AWD cars, but that is likely more to do with my skill level rather than the car's ability.

I was happy to find that the TC/SC on the RWD does allow a good amount of slip, particularly in these wet conditions. Love the feeling of rotating the back end out around the tight corners. Running the skinny 235/19 stock tires led to plenty of understeer as expected. My next investment will be a wheel and tire package for the track. I'm thinking 19x10 wheels with 275 tires.

Too much fun!!

 

[SammichLover]

You'll pay for the whole tire but you'll only use the edge! Needs camber badly! If you actually want to autocross it regularly you're going to want tires that are symmetrical side to side so they can be flipped left to right. I was running PS4S tires and I used 1/32nd of tread on the edge of the tire even with 8 laps in wet conditions and 4 laps in damp conditions.

TBF that's a known knock on PS4S tires. Awesome tire in a lot of ways but they are prone to chunking on the outside edge under stressful use.

I considered going with symmetrical tires for this reason, and expect to for the next set, but I went a different direction with my first set. Half-ish price, pre-rounded corners. Can't wear out what ain't there to start with! :^) Falken RS615K (not the "+"), $500 for the set. Here they are after noob abused overdriving, four laps at 85F and sunny on high grip concrete. I ran them at 38 PSI front and rear.
Rear:
Front:

Clearly the front took a lot more abuse, you can see I touched the first molding ridge with wear. I'm not even sure the rears fully warmed up. Their PSI didn't rise more than 0.5PSI total, while the front rose 1 to 1.5 PSI per run (which I then bled).

When I get the corner right, which isn't often yet, the car really digs in and turns. I'm just starting to get the hang of shifting the weight properly to get full grip, it's completely different than habits learned when driving on the street because of stop signs and The Man expecting me to slow down well below my tire's ability when making a corner, leading to learned behavior of getting back on the accelerator far too soon.

I haven't really noticed yet getting "held back" coming out of corners, even though I've gotten the car to noticeable oversteer at times. The "held back" might be masked by my self-induced oversteer w/too early acceleration? I have had the nanny total shutdown acceleration a few times on the MXM4s, but it was due to very clumsy driving that totally deserved it.

P.S. I have a picture of the outside edge of the MXM4s after four laps, on a much cooler day, but not sure I should post here as they are NSFW.

 

[GregRF]

P.S. I have a picture of the outside edge of the MXM4s after four laps, on a much cooler day, but not sure I should post here as they are NSFW.

Post!

 

[SammichLover]

Post!

Well ok, hopefully won't get banned for it.

For some reason the camera was a bit out of focus, and I didn't notice at the time to retake the photo, so you can't fully see the tire surface damage details (and of course the stench coming off them). You can however see clearly where the road contact came down to as it's much darker. This was taken in grid immediately following the last or second last run.

<edit> Brain fart. Must have been second last because I'd have driven past grid into the paddock after the last lap.



The white is a stray mark from me chalking the tires earlier to try get an idea about PSI. I think that was all just whizzing into the wind, though.

 

[Daniel in SD]

Recommend 255/40/18 or 265/35/18?

I'm running PS4S 265/40R18 18x9.5 TSW Bathurst +39mm offset. They have identical outside diameter to stock. Maybe running smaller diameter tire (shorter sidewall 18") would give slightly faster acceleration and lower ride height.
I would only autocross using the PS4S tires in the rain. Like I said, I think they only took about 1/32nd of damage. They stayed cool because of the damp pavement, so no chunks missing.

Nice job. Tires look trashed. What tires are they? What is the plastic on the fender....stone protection? Did you activate slip start...would that be helpful at all? Did traction control cut power that you noticed?

I've done that autocross a few times in an M Roadster and M3 years ago. As I recall at least back then, the course was wide open enough to get into 3rd gear, which is a bit more fun for those in heavier more powerful car

I didn't try slip start but I don't think it would do anything. Traction control was cutting power all the time, very noticeable. I'd be pressing on the throttle out of a corner and it would wait until the car was going close to straight to give me juice.

 

[AlanSubie4Life]

Traction control was cutting power all the time, very noticeable. I'd be pressing on the throttle out of a corner and it would wait until the car was going close to straight to give me juice.

Hmm, that sounds like the Chevy Spark EV. Clearly, on my single lap without Track Mode, I was not giving it enough juice, since I really didn't notice the cut in power...though maybe they tune traction control differently on Performance, even without Track Mode (I doubt it, but really no idea)? Mostly I just noticed a lot more understeer. The car seems to let that tail fly a bit in Track Mode (at least I think that's what is happening...time hasn't slowed down for me at autocross yet...need more seat time)... I assume the occasional clunking as I applied power through the corners was related...

 

[SammichLover]

I didn't try slip start but I don't think it would do anything.

I've tried it off and on, just 'cuz. Couldn't notice any difference but if there was anything it's probably subtle enough that I personally wouldn't be able to sort it out.

 

[SammichLover]

Traction control was cutting power all the time, very noticeable. I'd be pressing on the throttle out of a corner and it would wait until the car was going close to straight to give me juice.

Different tires but coming out of a hairpin right after the start gate, into a longish straight, I was able to get oversteer and full accelerator was responding through it at least close to normal, if not normal. I really need to get a G-force reading data logging tool of some sort.