Dream Edition aiyoooo!

[borski]

I’ve been told that the DE has the rear motor of the GT in both front and back. The GT has a different motor for the front, somewhat less powerful. I am not a power electronics or motors guy, so that’s as far as my knowledge goes there at the moment.

 

[californiaboy935]

I’ve been told that the DE has the rear motor of the GT in both front and back. The GT has a different motor for the front, somewhat less powerful. I am not a power electronics or motors guy, so that’s as far as my knowledge goes there at the moment.

Is this the Dream Edition of the Sedan? Or the Dream Edition of the Gravity you are talking about?

 

[Elfin]

I’ve been told that the DE has the rear motor of the GT in both front and back. The GT has a different motor for the front, somewhat less powerful. I am not a power electronics or motors guy, so that’s as far as my knowledge goes there at the moment.

That makes economic sense but it's definitely not a "compromise nothing" design. It means the extra power will be useful in a straight line with good traction. The Air Sapphire has twice as much power in the rear as the front.

 

[hmp10]

I’ve been told that the DE has the rear motor of the GT in both front and back. The GT has a different motor for the front, somewhat less powerful. I am not a power electronics or motors guy, so that’s as far as my knowledge goes there at the moment.

That would square with what @Adnillien posted about the MOSFET configuration, as it avoids having to tamper with the rear power unit while also avoiding a more powerful motor on the front axle.

It also might explain why the upcharge for the DE was less than I had anticipated.

I'm wondering if the front motor of the GT is the Atlas motor?

 

[hmp10]

I'm also wondering what the torque figures are for the DE and what the torque split will be front to back. If I recall, the OoS test drive video said the GT had around 970 lb/ft but didn't give an split figures?

 

[borski]

Is this the Dream Edition of the Sedan? Or the Dream Edition of the Gravity you are talking about?

Gravity.

 

[borski]

I'm wondering if the front motor of the GT is the Atlas motor?

It is not.

 

[borski]

That makes economic sense but it's definitely not a "compromise nothing" design. It means the extra power will be useful in a straight line with good traction. The Air Sapphire has twice as much power in the rear as the front.

My understanding is they’re, uh, quite smart about how and where they apply that power. But I haven’t driven a DE Gravity, so I couldn’t tell you from experience.

I can also say the DE was something Peter really wanted, and given that he’s a “car guy’s car guy” I’m not that concerned.

 

[Denali_Dane]

If @Denali_Dane rigs up a bear shaped puddle light that can be added to the Air, I want one!

I can see if I can make it happen.
It will definitely be with the California Racing Bear

 

[hmp10]

My understanding is they’re, uh, quite smart about how and where they apply that power. But I haven’t driven a DE Gravity, so I couldn’t tell you from experience.

I can also say the DE was something Peter really wanted, and given that he’s a “car guy’s car guy” I’m not that concerned.

Any word on when the press might get its hands on a GDE for a test drive?

 

[Murcie]

Any word on when the press might get its hands on a GDE for a test drive?

I know things might be different now, but was the press ever given an Air DE to review? Was it offered for test drives? Or it was exclusive to those who ordered it?
I’m speculating but I think Gravity DE deliveries will happen very soon, before press reviews and test drives at Studios for holders of GT orders.
Maybe they’ll let the press review the GT under embargo, and deliver the DE’s on the same day the embargo is lifted, for both events to happen at the same time to have a bigger impact

 

[hmp10]

I know things might be different now, but was the press ever given an Air DE to review? Was it offered for test drives? Or it was exclusive to those who ordered it?
I’m speculating but I think Gravity DE deliveries will happen very soon, before press reviews and test drives at Studios for holders of GT orders

Yes, several reviewers were. The most notable was "Motor Trend's" Jonny Lieberman who test drove a Eureka Gold one from L.A. to San Francisco and later took it on a lengthy hill and canyon run outside of L.A.

 

[Neurio]

And Tom Moloughney did his 70 mph range test with a DE-R and got over 500 miles

 

[Elfin]

My understanding is they’re, uh, quite smart about how and where they apply that power. But I haven’t driven a DE Gravity, so I couldn’t tell you from experience.

I can also say the DE was something Peter really wanted, and given that he’s a “car guy’s car guy” I’m not that concerned.

Peter probably wanted to put the dual rear motor in it. Smart about applying power means not using the power in the front while turning. Obviously it's not going to be worse than the GT, it's just not optimal.

 

[borski]

Peter probably wanted to put the dual rear motor in it. Smart about applying power means not using the power in the front while turning. Obviously it's not going to be worse than the GT, it's just not optimal.

Maybe. It also has RWS, which does change the dynamics too.

 

[MeganT]

Okay so I have to ask all those who have ordered the Dream Edition, why is it that ALL of you have chosen green with Tahoe interior? Perhaps it is due to our genetic hatred of the color orange, but my entire family has a knee-jerk reaction to the Tahoe that is not positive lol. I even drove back down to the showroom yesterday to look at it again in person to see if I was just misremembering my reaction to it. I definitely get that it's worth more than their only other option and it's essentially throwing away money to order the white Purluxe on the DE (and thus why I'm still here debating about the upgrade), but is there some other reason for the attraction to Tahoe? (and the Tahoe/green exterior combo)? I know lots of high end luxury cars are doing a similar shade in their cars. That it? Or is it just my family as an outlier in their love for this shade (surely possible lol)?

 

[Elfin]

Maybe. It also has RWS, which does change the dynamics too.

Nothing can change the basic physics that the front wheels have much less traction than the rear wheels under acceleration.

Weight transfer - Wikipedia

en.wikipedia.org

There are no high power performance cars that have equal front and rear power.

 

[hmp10]

Nothing can change the basic physics that the front wheels have much less traction than the rear wheels under acceleration.

The rearward weight shift can be affected significantly by the anti-squat characteristics of the suspension. My guess is the Gravity's adjustable air suspension will help keep squat to a minimum under acceleration. Even the Air with its coil spring suspension has very good anti-squat and anti-dive geometry. (The reason Lucids have relatively large rear brakes compared to the front brakes is that they dive less under braking, thus putting more braking load on the rear than most cars. The opposite applies to the squat control under acceleration. The front wheels do more of the work than in cars with less squat control.)

 

[PetevB]

The rearward weight shift can be affected significantly by the anti-squat characteristics of the suspension.

Not true. The weight transfer to the rear is a pretty simple physics problem that involves the height and longitudinal position of the center of gravity, the wheelbase and the longitudinal G forces. To use simple numbers if the center of gravity is 1 meter high and 1 meter in front of the rear axle then 100% of the weight will transfer to the rear axle at 1 G of acceleration (and you’ll begin popping a wheelie beyond that).

Traction is more complex, and there things like damping, spring rate and anti-squat come into play, but if anything anti-squat makes the rear stiffer decreasing available traction.

That said the gravity has a very long wheelbase of nearly 120”, and it also has a very low CG height (not sure what it is, but it’ll be lower than most ICE cars due the battery pack in the floor). This will help reduce weight transfer and make equal torque front and rear less bad. It will still be sub-optimal though; ideally something closer to a 60/40 power split would allow more acceleration around the traction limit. That may only be out of corners depending on the torque the gravity makes at the wheels, however- the rear likely has traction reserve in a straight line the way it’s “geared”, and that motor used at the front might still be below the limit of the tires in good conditions.

 

[hmp10]

Not true. The weight transfer to the rear is a pretty simple physics problem that involves the height and longitudinal position of the center of gravity, the wheelbase and the longitudinal G forces. To use simple numbers if the center of gravity is 1 meter high and 1 meter in front of the rear axle then 100% of the weight will transfer to the rear axle at 1 G of acceleration (and you’ll begin popping a wheelie beyond that).

Traction is more complex, and there things like damping, spring rate and anti-squat come into play, but if anything anti-squat makes the rear stiffer decreasing available traction.

That said the gravity has a very long wheelbase of nearly 120”, and it also has a very low CG height (not sure what it is, but it’ll be lower than most ICE cars due the battery pack in the floor). This will help reduce weight transfer and make equal torque front and rear less bad. It will still be sub-optimal though; ideally something closer to a 60/40 power split would allow more acceleration around the traction limit. That may only be out of corners depending on the torque the gravity makes at the wheels, however- the rear likely has traction reserve in a straight line the way it’s “geared”, and that motor used at the front might still be below the limit of the tires in good conditions.

I'm no engineer, and your post caused me to dig into the issue a bit more. I found conflicting views, but some claim that squat does affect rearward weight transfer, such as this one:

How does Anti Squat work?

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My comment about the braking behavior came from an answer Eric Bach, Lucid Chief Engineer, gave to a reviewer who was asking about the unusually large rear discs and calipers on the Sapphire. Bach said that the low center of gravity reduced braking dive, thus putting more braking load on the rear wheels.

In any case, I'll defer to you, as you appear to know considerably more about this than I.