Confirm some MX 8.0 findings

[vv132]

Hey guys got a couple drives in today with the Model X 8.0 firmware. Wanted to confirm some points/changes I noticed. Please confirm /comment.

1. Active Spoiler now fully opens 0-45mph ish and then reduces to 20% open when above 50mph (my estimate). This was not how it was before the update. Is this better or worse for drag?

2. Side Car Collision Avoidance option is now not present in the settings menu...what happened to it

3. Driver side FWD detects obstacles when closing ( thought this was fixed last fw but now phantom ghost objects are back)

4. Slacker/Tunein not logged in ...(where do you guys find the account info in your paperwork)

5. AutoPilot non detection of car changing lanes infront when car is real close to the front left or right (not in camera view ) and then moving infront in same lane.

Thanks for any inputs.

 

[Hitman007]

I can confirm that my 8.0 update did not cause any of these items except #1 (I don't have active spoiler) and #2. I was not aware of this setting before. My Tunein is still logged inm FWD works fine and autopilot is working perfectly.

 

[passcore]

I have #3 above after the 8.0 upgrade although I have never had any prior issues with the FWD. Dropped the car off at the SC yesterday and will be picking up tomorrow.

 

[travwill]

#4 Streaming (Slacker) and TuneIn - if you scroll to bottom you see the note that you can login with your own account if you want. If not, its using the free Tesla provided/free account. Benefit of if you login is that if you make lists/favorites in you car and from your phone/Mac/PC, then they all remain in sync. I don't think the high quality settings make much of a difference with premium memberships.

 

[NovemberXray]

Active spoiler has always been in upright position at speeds below 45 and lowers at higher speeds. This improves visibility at slow speeds and effectiveness at high speeds.

I have had no issues with 8 on my X.

 

[CmdrThor]

I have #3 above after the 8.0 upgrade although I have never had any prior issues with the FWD. Dropped the car off at the SC yesterday and will be picking up tomorrow.

Surely you had an appointment scheduled weeks ago and just happened to add this to the repair order?

If not, then that is amazing because non-critical issues have been around 3 weeks to get an appointment at Marietta recently.

For the OP, I haven't noticed a change in the active spoiler, but I would assume if they made a change it is for better efficiency.

I've never seen the Side Car Collision Avoidance setting.

No phantom obstacles, but I had my falcon wing door sensors replaced before the update that apparently removed their usage. Maybe those sensors are being used again and mine are in good shape because they were replaced recently.

No slacker or tunein issues. I believe there is a reset procedure, or you can just email service and they will give you your slacker login.

I haven't had any autopilot issues, but I've driven less than 200 miles on 8.0, maybe 75-100 on autopilot.

 

[K-MTG]

was #2 ever an option?

 

[passcore]

Surely you had an appointment scheduled weeks ago and just happened to add this to the repair order?

If not, then that is amazing because non-critical issues have been around 3 weeks to get an appointment at Marietta recently.

For the OP, I haven't noticed a change in the active spoiler, but I would assume if they made a change it is for better efficiency.

I've never seen the Side Car Collision Avoidance setting.

No phantom obstacles, but I had my falcon wing door sensors replaced before the update that apparently removed their usage. Maybe those sensors are being used again and mine are in good shape because they were replaced recently.

No slacker or tunein issues. I believe there is a reset procedure, or you can just email service and they will give you your slacker login.

I haven't had any autopilot issues, but I've driven less than 200 miles on 8.0, maybe 75-100 on autopilot.

Nope. Called at 8am on Monday and dropped off my car at 1pm the same day

 

[FarmerDave]

I've had several occurrences of #3. Please post what the Service Center solution is (and if it works).

 

[Gerasimental]

Wait, the spoiler goes DOWN at high speeds?
The point of an active spoiler is usually to generate increasing downforce at high speeds for improved high speed handling and stability.
Of course lowering it at high speed helps to reduce drag, but also eliminates the whole point of the spoiler, to generate downforce.

At low speeds it does next to NOTHING (downforce and drag are negligible relative to mass and inertia of the car), and high speeds its retracted.

Wtf is this spoiler for then? In early 2015 I was already arguing that there was probably no need for a spoiler from an engineering standpoint, this seems to confirm it.

 

[jonman]

Wait, the spoiler goes DOWN at high speeds?
The point of an active spoiler is usually to generate increasing downforce at high speeds for improved high speed handling and stability.
Of course lowering it at high speed helps to reduce drag, but also eliminates the whole point of the spoiler, to generate downforce.

At low speeds it does next to NOTHING (downforce and drag are negligible relative to mass and inertia of the car), and high speeds its retracted.

Wtf is this spoiler for then? In early 2015 I was already arguing that there was probably no need for a spoiler from an engineering standpoint, this seems to confirm it.

this is why i opted for the fixed spoiler. i've seen that the active spoiler is not truly doing the job of a spoiler. that said, the moving of a spoiler higher and higher at faster speeds isn't better due to increased drag and too much down force. indy cars are the best example with their crazy spoilers giving them down force around 3Gs. that's just crazy.

without going into the detailed specs of vehicle weight, the actual down force applied, and amount of drag reduced i'm just going to say that i don't believe that Tesla found the right relationship with the lift/drag ratio.

fixed spoiler FTW

 

[CmdrThor]

Wait, the spoiler goes DOWN at high speeds?
The point of an active spoiler is usually to generate increasing downforce at high speeds for improved high speed handling and stability.
Of course lowering it at high speed helps to reduce drag, but also eliminates the whole point of the spoiler, to generate downforce.

At low speeds it does next to NOTHING (downforce and drag are negligible relative to mass and inertia of the car), and high speeds its retracted.

Wtf is this spoiler for then? In early 2015 I was already arguing that there was probably no need for a spoiler from an engineering standpoint, this seems to confirm it.

The spoiler doesn't go all the way down at higher speeds, it is partially lowered. It can't go all the way down because the middle brake light is on the spoiler.

this is why i opted for the fixed spoiler. i've seen that the active spoiler is not truly doing the job of a spoiler. that said, the moving of a spoiler higher and higher at faster speeds isn't better due to increased drag and too much down force. indy cars are the best example with their crazy spoilers giving them down force around 3Gs. that's just crazy.

without going into the detailed specs of vehicle weight, the actual down force applied, and amount of drag reduced i'm just going to say that i don't believe that Tesla found the right relationship with the lift/drag ratio.

fixed spoiler FTW

By opt for the fixed spoiler do you mean you ordered a P90D (or P100D) and opted out of the active spoiler? Or you just ordered non-performance and just didn't get the active spoiler? There is a setting that makes the active spoiler act like the fixed spoiler while driving, but it still retracts when the car is locked. You just change the spoiler mode from automatic to extended.

 

[jonman]

The spoiler doesn't go all the way down at higher speeds, it is partially lowered. It can't go all the way down because the middle brake light is on the spoiler.



By opt for the fixed spoiler do you mean you ordered a P90D (or P100D) and opted out of the active spoiler? Or you just ordered non-performance and just didn't get the active spoiler? There is a setting that makes the active spoiler act like the fixed spoiler while driving, but it still retracts when the car is locked. You just change the spoiler mode from automatic to extended.

the 90D. maybe someday Elon will make the performance upgrades affordable

 

[Gerasimental]

The spoiler doesn't go all the way down at higher speeds, it is partially lowered. It can't go all the way down because the middle brake light is on the spoiler.

I realise that but I suspect that at 20% lift, the lift on the aerofoil is minimal due to the low angle of attack as well as reduced airspeed in the boundary layer near the car.
The fact that the spoiler retracts at high speeds and stands tall at low speeds suggests to me that its presence has little to do with vehicle dynamics.

 

[MXadopter]

My experience:

#1 I believe that the spoiler behavior has always been this
#2 I do not ever remember seeing this option...
#3 Fortunately no issues yet with phantom objects
#4 No Change for streaming settings/login
#5 AP seems to be overall quite a bit better/more confident on my end.

It's only been a few days for me so let's hope all is well.

 

[NovemberXray]

I realise that but I suspect that at 20% lift, the lift on the aerofoil is minimal due to the low angle of attack as well as reduced airspeed in the boundary layer near the car.
The fact that the spoiler retracts at high speeds and stands tall at low speeds suggests to me that its presence has little to do with vehicle dynamics.

As mentioned above, the spoiler does not retract at high speed, it changes angles. Based on the steeply sloped roof and the way the the is flowing over the vehicle, it seems to me that this makes perfect sense. In the high speed mode the spoiler is angled more in line with the window, which should allow it to scoop more air and produce greater down force. In the fully raised position more air is going to go over the top of the spoiler rather than under it, as it's nearly level with the ground and presenting the top surface to the airflow.

That being said, this would really depend on the design of the spoiler, which I am now going to look at much more closely when I next go out to my car. You may be right that it's purely cosmetic, because if it does have an air foil, I don't think it's very defined. If it's just flat, then increasing air flowing over it would not help, on the other hand if it IS a true spoiler/wing/airfoil then I believe angling it up to catch more air might actually make the wing more effective. As a pilot I'm much more familiar with lift, so I'm just trying to think upside down.

Now I have to go search, would love to see some video of airflow modeling on the Model X in a wind tunnel!

 

[Gerasimental]

Now I have to go search, would love to see some video of airflow modeling on the Model X in a wind tunnel!

All good points, but in particular amen to this.

Could you take a pictures of the spoiler in profile on your car?

 

[NovemberXray]

OK, here's some pictures. Unfortunately I can't get it in the lowered "high speed" position, but you can picture it, it's pretty much parallel with the rear window in that mode.

The spoiler does not look like much of a foil to me, it is thinner at the leading edge, but both sides are flat, so I don't think it's functioning like a wing. Only thing that makes any sense to me would be that in the high speed position it's funneling more air under the spoiler which is then deflecting off that serious lip at the bottom of the window, which is flush with the spoiler when it's retracted, presumably that would have SOME effect, not sure how much though. Again, would love to see this thing modeled in a wind tunnel. Sadly I can only find stuff about the Model S.

 

[aesculus]

Wait, the spoiler goes DOWN at high speeds?
The point of an active spoiler is usually to generate increasing downforce at high speeds for improved high speed handling and stability.
Of course lowering it at high speed helps to reduce drag, but also eliminates the whole point of the spoiler, to generate downforce.

At low speeds it does next to NOTHING (downforce and drag are negligible relative to mass and inertia of the car), and high speeds its retracted.

Wtf is this spoiler for then? In early 2015 I was already arguing that there was probably no need for a spoiler from an engineering standpoint, this seems to confirm it.

I don't have the energy to search for you but last fall this was debated endlessly. The spoiler in the Model X is not designed to increase downward force for handling. It was designed to improve airflow. It's only supposed to boost range by a few miles so it's not a big contributor.

 

[Xminus6]

I don't have the energy to search for you but last fall this was debated endlessly. The spoiler in the Model X is not designed to increase downward force for handling. It was designed to improve airflow. It's only supposed to boost range by a few miles so it's not a big contributor.

I can't imagine that tiny spoiler on the back of a >5000# car would make a whit of difference in downforce. It's much more likely, as you state, that it's simply to improve the airflow off the back of the car and improve aerodynamics slightly.