The REAL top speed of the Model S

The REAL top speed of the Model S

So, we all know that the top speed of the Model S is software-limited to around 130mph (depending on model/options)...If there was no software limitation, what do you think the real top speed of the Model S would be. I would think pretty high, considering the 416hp/443ft-lb torque, even considering the weight of the car. But if you had to pick a number, what would you guess? (Anyone out there "jailbreak" their S yet?!?!)

And, why do they limit the top speed in the first place? Is it vehicle/passenger safety? Is it to specifically protect the life of the batteries? Would it be too difficult to properly cool the battery pack while going 160, 180, 200mph? Not that you could even drive at that speed for a significant amount of time. But still...

Just wondering. Any thoughts?

Brian H | May 28, 2013

It's a one-speed gear reductions system, so there's a motor RPM limit.

TheAustin | May 28, 2013

That may be the case, but what does that specifically mean with regards to the top speed limitations? Is 130 mph the limit of the gear reduction system? And if so, why does Tesla's terminology specifically say "software-limited?"

lolachampcar | May 28, 2013

Motor RPM proportional to car speed. Limit car speed, limit motor rpm. As Brian said, there is only so fast you can spin the motor thus only so fast you can go in the car.

There may also be a peak discharge rate for the pack as well.

George with SacEV | May 28, 2013

The load on the battery going hard from 0 to 60 or 100 mph seems like it would be less than holding some level of "top speed." What am I missing? As noted, the specs for the Model S indicate top speed is software limited, but sometime, somebody, is going to want to find out how fast this thing CAN go, even briefly.


Andre-nl | May 28, 2013

I am nearly sure the Model S is software limited, not rpm limited.

If that were the case, then: acceleration when nearing 130 mph would be incredibly slow as the motor would be hitting its rpm limit.

It might be 'rpm limited' in the sense that it explodes from centrifugal forces once you go above a certain rpm, but I imagine Tesla would design in a certain safety margin ;)

jat | May 28, 2013

@gparrott - drag goes up with the square of velocity, and at 100mph virtually all of the power used is overcoming drag. The Bugatti Veyron doesn't have 1000hp just for 0-60 times, but for overcoming drag at high speeds.

Litennn | May 28, 2013

130 MPH is maximum impulse speed in the atmosphere, you cannot jump to warp speed while still in the earths atmosphere due to rotational speeds of motor armature in earths gravity.

ajamison | May 28, 2013

Honestly when I get my Model S (eventually I will own one that is my goal in the immediate future) I am not likely to go anywhere near 130 but I can see someone in the UK specifically around the autobon that might want to know the answer to this since if I am not mistaken the Autobon has no speed limit.

Andre-nl | May 28, 2013


It is said that in certain locations there are ripples in the fabric of spacetime, where you can jump great distances in an infinitesimally small timespan. Some call those anomalies wormholes, others Autobahn.

BYT | May 28, 2013

We need an Autobahn in the US, can I suggest between San Francisco and L.A. with a power strip running down the highway for the Model S to charge and she charges down the road? :)

ajamison | May 28, 2013

I am waiting for Elon to introduce a Static electricity charging system so you can charge from the ambient electrical charge in the air. :)

Andre-nl | May 28, 2013

Or rub it with your cat.

lph | May 28, 2013

I believe the software rpm limit has to do with stopping damage to the windings (centripital action).

David59 | May 28, 2013

lph I was told that the windings were on the outside and were stationary so the only moving part of the motor is the magnet. If that is true it makes for a very robust electric motor.

Brian H | May 28, 2013

The software limitation is there to protect the motor against irresponsible drivers like you guys. >:(

Superliner | May 28, 2013

An "unlimited" EV-1 managed 183 mph. with a stock drive train and a minor modification "add on" to reduce turbulence at the rear of the car.

Robert22 | May 28, 2013

That would significantly improve my commute :)

jbunn | May 28, 2013

The motor does not have permanent magnets. I saw a cutaway at the Bellevue store and looked to me like the winding was on the rotor. Hmmm...

The motor takes variable speed alternating current. Higher frequency makes the motor spin faster. Easy to limit the RPM by limiting the maximum frequency the power module will put out.

RZT5 | May 28, 2013

IMO, assuming Tesla limited speed to prevent over revving the motor, the best way to get more top end speed out of the Model S would be with a modified, or completely new gearbox. Of course this wouldn't be cheap, aftermarket limited production gearboxes used in racing can cost as much as an entire Model S.

Timo | May 29, 2013

At very high RPM motor torque drops, you no longer have that 400+ HP at 14k RPM. It might be that Model S real top speed isn't much higher than that 130mph, unless you tweak with gears (or gear in this case). OTOH with smaller reduction you drop torque at the wheels, so there is upper limit in that too. Finding the perfect gear rating for maximum top speed would require some fancy math (or trial and error -method).

Brian H | May 29, 2013

With a lower reduction ratio (TM is 9.7:1) you can get higher top speed, but lower range accel suffers. Pick one.

George with SacEV | May 29, 2013

I agree in terms of wanting optimal acceleration within the typical range of used speed.

HOWEVER in response to one of the observations above....given that the Performance version of the Model S has 416 hp and a rather low coefficient of drag....this level of power should be capable of upwards of 160 mph, given comparisons with other vehicles of less aero design and comparable horsepower?

A 565 hp Aston Martin that was just introduced in the last couple of days has a claimed top speed of 205 and it is not as aero as the Model S, and what is the top speed range of the Panamera? The 400+ hp range of that model is good for upwards of 165mph.....

Just curious.......

Tiebreaker | May 29, 2013

The Tesla motor has no permanent magnets.

The windings are in the stator.

The rotor is a copper cylinder, no windings. Featured in the "Mega Factories" video:

Brian H | May 29, 2013

How many gears does the Aston have? What's the difference in reduction ratio between 1st gear and top gear.

Irrelevant to the MS. Even the Roadster broke every transmission that tried to put gears in the car.

Brian H | May 29, 2013

typo: ... top gear?

alcassfast | May 29, 2013

@Brian H,

Don't say those words!

Brian H | May 29, 2013

I was careful not to capitalize.

Dr. Bob Reinke | May 29, 2013

I believe the speed limitation is a safety consideration. The copper armature is very heavy and soft. Soft Copper makes an exellent and powerful rotor. I've seen what can happen to a loose steel flywheel in a dragster at about 8,000 rpm. Shredded the cast iron bellhousing, then virtually cut the car in half, killing bystanders over 500 feet away. Try to picture Copper, at much greater molecular weight, in tons, slashing through everything in the way, including the passengers in the Model S, and nearby cars and bodys. Would make bad headlines. I have seen an electric motor armature disintergate in lap tests. I believe, without lab tests, that the Tesla motor is governored at substantially less than the point of centrifugal disintegration. | May 29, 2013

Assuming you can bypass the software speed limiter (which I really doubt), the issues that could cause critical failures that are not a concern below the speed limit:

1) Heat generated by the motor, inverter and/or gears exceed limits and parts melt.

2) Electronic drive components are driven beyond there design limits and fail.

3) Vehicle stability systems are not tuned to these higher speeds and unexpected problems may develop due to these systems.

4) At some point the centrifigal forces rip the motor apart.

5) Oil in the gear case starts foaming, causing loss of useful lubrication (with failure to occur soon after).

6) Rotational parts could hit a resonant frequency not encountered at lower speeds and cause all sorts of catastrophic problems.

All these sound very costly if they occur. I'm sure there is a design safety margin for all these situations, and the software does monitor issues like heat to help prevent some of these types of failures. Still, it's not a lot different than pushing a ICE car beyond it's design limits - usually something fails, and often catastrophically.

I think it may be hard to find someone willing to take these kinds of risks with their own MS, but good luck!

Olof | October 22, 2013

I read in a TM investor presentation that the MS motor is limited to 18000 rpm. That means 1849 wheel rpm at the reduction of 9.73:1 and at a wheel diameter of 27,7" gives you a speed of

drum roll... 152,8 mph!

If the motor has enough torque at 18000 rpm to drive at that speed I don't know.

DonS | October 22, 2013

I calculated top speed using the 0.24 drag coefficient and assuming 4800 lb curb weight with a driver. There is also a nominal value included for rolling resistance. 416HP would get a top speed of just over 200 mph, but would need lower gearing to avoid destroying the motor and a really long straight away.

Here is a calculator I used:

DonS | October 22, 2013

Also, I used a frontal are of 28.8 square feet.

George with SacEV | October 22, 2013

It would seem that IF Tesla/Musk wants to impact the GERMAN Luxury/Performance sedan market, it/he will have to retune the German Market cars for MUCH higher top speed in order to be attractive as autobahn cruisers.

I recall being passed on the German autobahn by a Ferrari going about 150+ mph ( I was going about 90 mph in a 1 day new 3-series BMW and he passed me like I was standing still) and the Ferrari was being tailgated by a 7 Series BMW about 18 inches off his rear bumper!

130 mph is for Fiats and Ladas on the Autobahn. No self-respecting upscale sedan driver accepts less than about 170 mph for at least brief rushes.

AmpedRealtor | October 22, 2013

According to Wikipedia, the average autobahn speed is 88 MPH and only 15% of drivers exceed 106 MPH. Over 60% drove at or below 81 MPH and approximately 30% drove at or above 93 MPH. I don't really think you'll be seeing Fiats going 130 MPH anytime soon, at least not according to this article.

Olof | October 22, 2013

@amped: agreed that you don't drive very fast for various reasons such as traffic or saving fuel, but having lived in Germany I know that most people want to feel that their car CAN go fast. A big powerful sedan ought to do at least 250kph according to Germans, at which speed most are governed (exception AMG, M, Porsche and so on)

Range would obviously be very short, but should TM still tweak MS to go 250kph to match? would be interesting to hear opinion on this

George with SacEV | October 22, 2013

I have driven a bit over 100 mph in a rental Fiat on the autobahn and towards the end of our breaking period with the 3-series BMW got easily up to around 125 mph on a rather busy section of that limit-free super highway. I was never the fastest car around at any time.

Vall | October 22, 2013

Most people also don't like stopping every 20 minutes to charge for 20 minutes. So raising the top speed, if possible at all, will have much more negative consequences than limiting it to 130 mph. The Model S is simply not meant for those people who MUST know their car can do 200 mph, even if they do it only once.

Olof | October 22, 2013

But you could instead of the extreme 200 limit to 155 and maybe have maybe get
30 minutes. Then your fellow Germans would respect your car even if you only maxed it out rarely

Vall | October 22, 2013

If your fellow germans are so shallow, then f*** your fellow germans. You think they won't die laughing when you tell them that it can barely do 30 min?

jcaspar1 | October 22, 2013

200 MPH seems VERY optimistic. The Mercedes SLR McLaren with 617 hp can barely reach 200, if at all. 155 I can see. Even a new Dodge Viper with 640 hp just gets to 207.

barbarajrosen | October 22, 2013

I was more interested in Musk's comments about the range of the new (cheaper) car-which he says will be AT LEAST 200 miles. I purchased a 40KW model before Tesla decided not to make this model. So, I ended up with a 60KW battery that they limit the charge capacity to 40KW. I was told that I could upgrade the battery for an additional $10,000. My effective range is slightly over 100 miles. I will be very interested in seeing how Tesla treats their early adopters who paid the high price when the less expensive version comes out. Perhaps they will have the decency to offer those of us with a 60KW battery limited to 40 KW power, a free upgrade. What's it to them? It costs them next to nothing to do this. I hope I don't end up regretting being one of the early supporters of the company. And yes, I do love my car-- other than the range limitation and the rear view mirrors that don't retract.

carlk | October 22, 2013

Someone told me there is the hierarchy on the Autobahn that drivers usually follow. VW will yield to BMW which will yield to Porsche. Elon just want to place the MS at a good position on the chart.

Pungoteague_Dave | October 22, 2013

There are plenty of cars in Germany that can do over 200mph. It isn't as rare as implied in this thread. Cars go that fast every single day. Germans and Europeans are more competent drivers on average, and slower cars spend more time watching the rear view than the forward view. Priority and lane change protocols are respected and there's no such thing as passing on the right. I was in a RUF Porsche last year as a passenger and did about 30 miles at 206mph in a convoy of other supercars. It is routine and I not think the S is up to that task no matter how well tuned. However it also isn't in the supercar price range.

jeffsstuff | October 22, 2013

I have a Lexus ES-350 (which I finally get to rid myself of when my Model S is delivered in December). It is "speed limited" as were my two prior BMWs. I believe that it has to do, not with RPMs or engine/motor limitations but rather with the tires. At least, that was what I was told years ago.

Also, just because I'm feeling moody...
"I am not likely to go anywhere near 130 but I can see someone in the UK specifically around the autobon that might want to know the answer to this since if I am not mistaken the Autobon has no speed limit."

While parts have no speed limit, I do believe it is not in the UK but rather in Germany.

martin0641 | February 16, 2014

It would be nice if all the white-knights would stop it with the hand wringing and moralizing over what is essentially a gearhead question.

No one is suggesting they want to drift through a schoolzone sideways at 200mph, people like understanding the technical boundaries of something and pushing the state of the art to the limit, which is why more than once during star Trek they had the thing floored to the point it almost shook apart.

Maybe Tesla should partner or start a Formula-E division team, and then we can all ponder the technical awesomeness without a bunch of hand-wringing about an endless list of what-its and maybes and why someone is or is not an irresponsible jerk because they dared to ask a question, even if they just want to take their car to a local track and see if they can get a visceral thrill without the negative baggage and risks that comes with doing so in a parking lot.

Nice to see the majority of the people treating the question with the proper theoretical respect, but there was just enough gross to catch my ire...

I think it would break 200 if Scotty disabled all the safety functions and drove it like it was the last time he ever expected it to start without major repairs...

EJH | February 17, 2014

Saleen will probably be providing answers to Model S top speed and acceleration possibilities.

jordanrichard | February 17, 2014

Top speed in the real world is just for bragging rights. Here in the U.S., you get caught doing 130 mph, you are going to jail. I too heard that the limits set on cars is based on the tires the manufacturer fitted to the cars. With that said, the manufacturers could have easily just spec'd out high performance tires.

As for the Autobahn, 60% of it has no speed restriction. I too have been on the autobahn traveling on the A8 to Stuttgart going 103 mph and got passed by a family on a VW van. I estimate they were doing about 115-125 mph.

As mentioned above, despite the autobahn for the most part having no speed limit, cars are governed to 155 mph. There is a "Gentlemen's Agreement" between MB, BMW, Audi etc. that "non-performance" sedans will not go faster than 155 mph.

Olof | December 2, 2014

So now that the 85 got a 140 Mph top speed, will the old ones get it too, in next software revision?

Brian H | December 2, 2014

Yes, the speedos will read 10% high.

annekristip | December 2, 2014

Not true for Model S, it reads maybe 1-2% high, most other cars have 5-10% high.