What if Tesla put a large motor in front to match P90D's large motor in back?

What if Tesla put a large motor in front to match P90D's large motor in back?

How fast would this Model S be in Ludicrous mode?

What would Tesla name this Model S?

How much horsepower and torque?

I would sacrifice front trunk space for a larger motor.

WHitchings | 28. februar 2016

I would assume Tesla has determined that the front motor produces all the useful torque it can, and given the reduced space the steering and cooling gear needs up front.

inconel | 28. februar 2016

Current limitation is the battery not the motors. We are already not able to make full use of the combined horsepower of the large rear motor plus smaller front one. | 28. februar 2016

Actually, you might get less performance and torque. Some of the reasons include:

More structure to hold the heavy motor
Higher weight of the motor and structure will reduce 0-60 times
The battery can only safely deliver power that is already below the current P90D's two motor capacity
Wheel traction is also already at the limit from about 0-30 (but larger/softer drag strip tires could help, but then would also add weight)
It's unclear if the battery/motor cooling system could protect everything if running at a higher power level (i.e. generating even more heat)

My take is you'd need to make a lot more engineering changes throughout the car than just switching the motor.

Son of a Gunn | 28. februar 2016

Better off putting two small motors on the front. Check out Rimac Concept_One. Both motors are indeoendent, a motor dedicated to a wheel but connected with a virtual (software) differential. Independent motors makes true torque vectoring possible as opposed to the more primitive brake torque vectoring. Imagine not just high speed super handling but also the ability to turn with much much tighter radius at low speeds for autonomous cars.

I can see Tesla doing this in 3 to 5 years, for sure.

cephellow | 28. februar 2016

Next level will be plaid. IMO, motor options should be 1,2,3 & 4; using the 225hp motor and having Siamese motor pairs, much like the NSX. The "ultimate plaid" version would have these Siamese units front and back. True torque vectoring and dedicated traction control on each corner, with lower pinion/primary bearing loading, lower rotational mass (no diff, smaller rotors) and benefits of scale by producing only one motor/inverter combination are among the advantages. Looking at the layout of the drive unit cases, Tesla clearly has left this as an option. I would expect to see this strategy used on the next roadster.

Son of a Gunn | 28. februar 2016

By the way, if you want two equal-sized motors, go for the 85D or 90D. The P versions repurposed the older motor and put it in the back, but the 85D/90D have the newer liquid-cooled motors symmetrically on front and back. Torque bias is more even and torque sleep can be used on front or back. The P has a rear bias and torque sleep only on the front motor. The P is also battery power limited as both motors exceed what the battery can deliver but in the 85D/90D both motors combined can take what the battery can deliver. I'm going with the 85D/90D for these reasons--I don't need Ludicrous, IMHO. I do want all wheel torque vectoring. Gearheads will go nuts over that.

mathwhiz | 28. februar 2016

...The front trunk would be even smaller. ;)

JiveMiguel | 28. februar 2016

It would be a 1000+ horsepower beast (!), but would have much lower range/overall utility.

flight505 | 28. februar 2016

"Current limitation is the battery not the motors. We are already not able to make full use of the combined horsepower of the large rear motor plus smaller front one."

Does this mean when a P85D with Ludicrous upgrades to a larger battery years away that the batteries will produce more horspower?

@ Son of a Gun

Virtual differentials? Very impressive. Would "virtual driveshaft" be accurate to describe our dual motor Tesla's?

Son of a Gunn | 28. februar 2016

There are real driveshafts on the Model S. They're called half-shafts.

Son of a Gunn | 28. februar 2016

On the Rimac Concept_One car with twin motors front and twin motors aft, there are no mechanical coupling, per se, but the twin motors share the same housing. Having one housing allows it to share one circuit for cooling, among other things. The motors are synchronized using what's called a virtual diff, basically software that informs one of the twin motors what the other side is doing. ICE diffs are history.

flight505 | 28. februar 2016

Yes, half shafts drive front and rear wheels. But, do engineers refer to the connection between front and rear wheels in a dual motor EV as a virtual drive shaft?

Son of a Gunn | 28. februar 2016

You tell me, you're the one who injected the term. I was talking about the virtual diff in the Rimac.