Gravity 75 mph Range

[boydracing]

If you have the patience, it is in this OOS 2-hour video:

I didn't mark the spot where they talk about it, but I think it was when they are going through the configurator and selecting the wheels.

BTW - I put Hankook Ion tires on my Mach-e, and they are great. I saw a 7% highway range improvement over the OEM tires. I find it very interesting that OOS/Lucid praise how well they handle, as I think they are more slick than the OEM tires they replaced, but certainly the efficiency is way better. I like them, though. They are very quiet.

I checked Tire Rack and they don't carry sizes that fit any of the wheels on the Gravity. So the base set must be an OEM special for Lucid, which I am sure will show up on Tire Rack eventually.

I am also going with the 20" wheels on Hankooks just for the snow performance (best of the bunch) and good for EV use. It snows here in Park City.

 

[boydracing]

I noticed that adding the third row knocks 3% off the EPA range estimate. This is very surprising., because I didn't think those seats would be very heavy. What happens to the range when you have seven people in the car?

Luckily for the range I am concerned about, steady state highway, weight has a minor impact, and the extra row should not impact range at speed.

In the OOS Gravity first drive video (not the podcast posted above), they discuss EPA range and how important keeping the weight down was for meeting the 450-mile range result. To me that means the city driving component is a significant contributor to the 450-mile range result, which consequently likely means highway range will be even worse than expected. Now I am second guessing the 80%, factor and maybe @hmp10 is right about it being closer to 2.4 mi/kWh. I hope this is not the case.

However, 80% of 437 is 350 miles, which is still good for me.

View attachment 25358

Does anyone have an answer if you order the 3rd row, can you remove and still be flat like not ordering the third row. I have a 55 lb and 14 lb dog that needs room in the back. I saw Kyle's video and when they stow the third row, it is very uneven.

 

[borski]

Does anyone have an answer if you order the 3rd row, can you remove and still be flat like not ordering the third row. I have a 55 lb and 14 lb dog that needs room in the back. I saw Kyle's video and when they stow the third row, it is very uneven.

You cannot remove the third row. I don't know about Kyle's video, but when the third row stows it is intended to be completely flat, and is intended to be level with the rest of the stowed cabin. The idea is that the entire cabin can be one flat space, for loading objects.

 

[hmp10]

Does anyone have an answer if you order the 3rd row, can you remove and still be flat like not ordering the third row. I have a 55 lb and 14 lb dog that needs room in the back. I saw Kyle's video and when they stow the third row, it is very uneven.

I saw a video recently that raised this point, and the narrator said Lucid told him there would be an accessory cover that filled in that gap to create a flat floor for things such as putting a camping mattress in the back.

 

[Elfin]

One thing I've been curious about is why cars drops so much efficiency at 80mph. Here is the Out of Spec data from their 10% challenge (80mph) and 70mph range test
2025 Air GT 4.3mi/kwh@70mph 2.9mi/kwh@80mph 48% increase in energy
2025 Taycan 3.7mi/kwh@70mph 2.7mi/kwh@80mph 37% increase in energy
2024 Model 3 LR RWD 4.9mi/kwh@70mph 3.3mi/kwh@70mph 42% increase in energy
This seems higher than one would expect even if all losses are aerodynamic drag! (80/70)^2 = 31% increase.
While typing this I think I may have figure it out... The 80mph number is power delivered from charger so it includes charging losses while the 70mph is efficiency from the battery. The difference still seems large.

My prediction for 70mph range
511mi for Lucid Air GT at 70mph
20% more frontal area
20% higher Cd
4% bigger battery
15% increase in energy 75 vs 70
511/1.2/1.2*(123/118)*(70/75)^2 = 322 miles
Hope it's better than that so I'm going to change my guess to 350mi

 

[hmp10]

One thing I've been curious about is why cars drops so much efficiency at 80mph.

Aerodynamic drag increases exponentially with speed. A doubling of speed, for instance, increases the drag fourfold. At highway speeds, aerodynamic drag becomes the single biggest force resisting the car's forward motion.

Have you ever stuck the flat of your hand out of a car window on the highway and felt the wind almost rip your arm out of its socket? Now, multiply the surface of your hand by the frontal area of your car and you'll get some sense of what your car is pushing against.

That's why Lucid spends so much time and effort trying to shave every little bit of frontal area off its cars and whittle away at the drag coefficient every way possible. It's one of those areas in which even seemingly insignificant differences can yield very significant differences in outcomes.

 

[Elfin]

Aerodynamic drag increases exponentially with speed. A doubling of speed, for instance, increases the drag fourfold. At highway speeds, aerodynamic drag becomes the single biggest force resisting the car's forward motion.

Have you ever stuck the flat of your hand out of a car window on the highway and felt the wind almost rip your arm out of its socket? Now, multiply the surface of your hand by the frontal area of your car and you'll get some sense of what your car is pushing against.

That's why Lucid spends so much time and effort trying to shave every little bit of frontal area off its cars and whittle away at the drag coefficient every way possible.

Yes, my question was why the efficiency drops more than the aerodynamic drag formula suggests it should.
One would expect a 31% increase in energy consumption per mile due to aerodynamic drag at 80mph vs. 70mph.
I think part of the answer is that OOS measures efficiency from the charger at 80mph and efficiency from the battery at 70mph.

 

[hmp10]

Yes, my question was why the efficiency drops more than the aerodynamic drag formula suggests it should.
One would expect a 31% increase in energy consumption per mile due to aerodynamic drag at 80mph vs. 70mph.
I think part of the answer is that OOS measures efficiency from the charger at 80mph and efficiency from the battery at 70mph.

Oh, now I see what you were getting at.

I'm no engineer, so I had to resort to the internet where I found this:

"At 80 mph, the drag is approximately 36% higher than at 70 mph because 80^2 / 70^2 = 6400 / 4900 = 1.306."