Model S Performance vs BMW M5

[dsm363]

So far, the videos available show the opposite. We should get a Model S out on the track with ChrisN in his M5
so we can show how much better the Model S is.

Can you provide the links? i've only seen that one video of the 0-100mph sprint where the Model S Performance won 2 out of 3 times.

 

[stopcrazypp]

Looking at the data, the Model S (both the standard 85kWh and Performance 85kWh) accelerates faster than the Roadster Sport in the top end. The Model S Performance starts to match the Roadster in 40-50mph (0.7 secs for both), until it surpasses it for 60-70 (1 secs vs 1.1 secs). The standard Model S matches the Roadster at 60-70 and is faster for 70-80 (1.3 vs 1.6). The Roadster accelerates slower than both past those speeds.

Looking at the acceleration data for the 2013 M5 vs the MSP, the M5 matches the MSP in acceleration (this is with 3.7 sec with launch control with a 0-30 of 1.5 vs 1.7), and starts surpassing it at 50-60 (0.8 vs 0.9) and again at 70-80 (1.1 vs 1.3) and beyond.

(warning: video autoloads in the following links).
http://www.motortrend.com/oftheyear...nd_car_of_the_year_tesla_model_s/viewall.html
http://www.motortrend.com/roadtests...orsche_boxster_spyder_comparison/viewall.html
http://www.motortrend.com/roadtests/sedans/1203_2013_bmw_m5_test/viewall.html

Incidentally there's a Boxster Spyder in the comparo with the Roadster and that uses the same engine as the Cayman S (the Cayman R having slightly more power and being slightly faster). It also does better than the Roadster at the higher speeds (it matches the Roadster at 60-70 and is faster for 80-90, 1.5 vs 2.1 secs).

So the Roadster would be weaker in tracks where there's less chances to go significantly under 60mph (40mph against the Model S Performance) because there would be little chance to use the low speed acceleration. The MSP will also likely perform worse than the M5 in tracks with little chance of speeds under 60-70mph.

Looking at the telemetry for the track, there's very little places where you hit under 60mph (it's turns 1,6,9 specifically) and there the Roadster's understeer will work against it. So the Roadster is expected to perform worse at this track (even without the reduced power in the way).

http://www.trackpedia.com/wiki/Mazda_Laguna_Seca_Telemetry_for_Porsche_993_1:39.8

Anyone with the software to look at Traqmate data can compare with the High Plains Raceway where the Model S vs Roadster took place (note that the route on the track day was different from the one on trackpedia):
http://www.trackpedia.com/wiki/High_Plains_Raceway
http://www.teslamotorsclub.com/showthread.php/10986-Model-S-vs-Roadster-on-the-Track

 

[chrisn]

@stopcrazypp: Really interesting analysis, but I think a potential flaw is that comparing 0-30 times is largely irrelevant on the track because you never go slower than say 20MPH on the tightest turn. You're never at zero RPM and you never need to drop the clutch and worry about hooking up for a good launch. The Roadster and MSP get to 15 MPH much faster than any non-AWD ICE car, but I think that edge is basically meaningless on the track.

Now, OTOH, totally linear TQ is an advantage for EVs on track because you are effectively always in the perfect gear and in the sweet spot of the RPM/TQ curve (up to the speed where the EV stops pulling as hard as the ICE competition). But, with turbo charged cars (flat TQ) and dual-clutch trannies (no penalty for shifting), this advantage, although still likely significant, is not nearly as significant as the 0-30 times might suggest.

BTW, I have TraqMate files for my M5. Would be great to get some from an MSP.

 

[stopcrazypp]

@stopcrazypp: Really interesting analysis, but I think a potential flaw is that comparing 0-30 times is largely irrelevant on the track because you never go slower than say 20MPH on the tightest turn. You're never at zero RPM and you never need to drop the clutch and worry about hooking up for a good launch. The Roadster and MSP get to 15 MPH much faster than any non-AWD ICE car, but I think that edge is basically meaningless on the track.

I certainly realize 0-30 is basically irrelevant for the track (it's obvious just looking at the telemetry, where at no point was the car slower than ~45mph), but I just pointed it out to make it clear that's where the Roadster has its biggest advantage (and also is where the MSP loses out to the M5 with launch control).

BTW, I have TraqMate files for my M5. Would be great to get some from an MSP

If we have both then we'll be able to clearly see where the strengths and weaknesses for both are.

 

[DaveN007]

Can you provide the links? i've only seen that one video of the 0-100mph sprint where the Model S Performance won 2 out of 3 times.

Video is in this thread. M5 turning casual sub 1:48 laps of Laguna Seca...a relatively tight and technical track.

- - - Updated - - -

Looking at the data, the Model S (both the standard 85kWh and Performance 85kWh) accelerates faster than the Roadster Sport in the top end. The Model S Performance starts to match the Roadster in 40-50mph (0.7 secs for both), until it surpasses it for 60-70 (1 secs vs 1.1 secs). The standard Model S matches the Roadster at 60-70 and is faster for 70-80 (1.3 vs 1.6). The Roadster accelerates slower than both past those speeds.

Looking at the acceleration data for the 2013 M5 vs the MSP, the M5 matches the MSP in acceleration (this is with 3.7 sec with launch control with a 0-30 of 1.5 vs 1.7), and starts surpassing it at 50-60 (0.8 vs 0.9) and again at 70-80 (1.1 vs 1.3) and beyond.

(warning: video autoloads in the following links).
http://www.motortrend.com/oftheyear...nd_car_of_the_year_tesla_model_s/viewall.html
http://www.motortrend.com/roadtests...orsche_boxster_spyder_comparison/viewall.html
http://www.motortrend.com/roadtests/sedans/1203_2013_bmw_m5_test/viewall.html

Incidentally there's a Boxster Spyder in the comparo with the Roadster and that uses the same engine as the Cayman S (the Cayman R having slightly more power and being slightly faster). It also does better than the Roadster at the higher speeds (it matches the Roadster at 60-70 and is faster for 80-90, 1.5 vs 2.1 secs).

So the Roadster would be weaker in tracks where there's less chances to go significantly under 60mph (40mph against the Model S Performance) because there would be little chance to use the low speed acceleration. The MSP will also likely perform worse than the M5 in tracks with little chance of speeds under 60-70mph.

Looking at the telemetry for the track, there's very little places where you hit under 60mph (it's turns 1,6,9 specifically) and there the Roadster's understeer will work against it. So the Roadster is expected to perform worse at this track (even without the reduced power in the way).

http://www.trackpedia.com/wiki/Mazda_Laguna_Seca_Telemetry_for_Porsche_993_1:39.8

Anyone with the software to look at Traqmate data can compare with the High Plains Raceway where the Model S vs Roadster took place (note that the route on the track day was different from the one on trackpedia):
http://www.trackpedia.com/wiki/High_Plains_Raceway
http://www.teslamotorsclub.com/showthread.php/10986-Model-S-vs-Roadster-on-the-Track

So the MSP and Roadster have the advantage on tracks where you come to a dead stop, and then drive slowly? Like golf cart paths and Autopia? :biggrin:

The above information seems to continue to bolster the point. Great for drag racing, not so good on race tracks. If you read the first post in this thread, it is an interesting conclusion to have reached.

Once again, I point out that track performance is largely irrelevant for people buying Tesla cars today and that it is an astonishing accomplishment to be as close as Tesla is to matching a hundred years of ICE development and racing heritage practically overnight. That is the real take away. We are "tech-ing" our way to a better automotive future. Imagine a "Moore's Law" at work in the car industry. We will look back and laugh at ourselves one day. (Those of us concerned that performance would have to be compromised.)

 

[stopcrazypp]

So the MSP and Roadster have the advantage on tracks where you come to a dead stop, and then drive slowly? Like golf cart paths and Autopia? :biggrin:

Speeds under 60-70mph are not necessarily dead stops or driving slowly. There are about three points at Laguna Seca under those speeds (which I pointed out), but it does also have a couple of straights where you can reach over 100 mph or close. A track with more turns (and short to no straightways where you can reach 100+mph) will give the Roadster a better chance to use its lower end acceleration. The Roadster does extremely well in autocross where the average speed is between 30-60mph.

 

[vfx]

So the MSP and Roadster have the advantage on tracks where you come to a dead stop, and then drive slowly? Like golf cart paths and Autopia? :biggrin:
...

Unfortunately the Roadster and MSP only excel in 98 percent of daily stop-light-acceleration driving. As for those that wish to race them they may indeed suffer on certain tracks.

 

[Anzir]

Although this is purely an academic discussion, it is absurd to think that the MSP could hold its own against the F10 M5 on a track. Even with 100% torque available at any speed, the Model S was not developed for the track, e.g. suspension, differential, brakes, etc. This makes it great at drag strips and stop lights, but it will not hold a candle on the track to the M5, which can run with the last generation Ferraris. And believe me, I'm as much of a fan of the MSP as you all are.

 

[Jason S]

So the net-net is use Roadster for autocross where the speed is a lower average and use an ICE for racetracks where time to reach 150mph (or so) is pretty important. The Model S is merely a nice car for everything in between?

I'm ok with that. :wink:

 

[chrisn]

Jason S: I suspect the M5 will be faster than the MSP at all speeds between autocross speeds and 150mph also. MSP will win short stop light racing (which I personally never do) but will likely lag the M5 in highway "passing power" (which I personally do daily).

 

[DaveN007]

So the net-net is use Roadster for autocross where the speed is a lower average and use an ICE for racetracks where time to reach 150mph (or so) is pretty important. The Model S is merely a nice car for everything in between?

I'm ok with that. :wink:

I thought the net-net was that it turns out that the M5 outperforms the MSP with one possible exception- street drag racing. The "absurd and academic discussion" was started by Tesla fans asserting something very different. I was super curious about this because I have vicarious experience with the M5 (brother's car) and I was stunned to hear that Tesla had matched it. So it turns out that the MSP isn't quite there yet. A similar assertion was made regarding the Roadster. We should feel good about celebrating what these cars are and not keep trying to make them out to be something that they are not. :biggrin:

 

[brianman]

I thought the net-net was that it turns out that the M5 outperforms the MSP with one possible exception- street drag racing. The "absurd and academic discussion" was started by Tesla fans asserting something very different. I was super curious about this because I have vicarious experience with the M5 (brother's car) and I was stunned to hear that Tesla had matched it. So it turns out that the MSP isn't quite there yet. A similar assertion was made regarding the Roadster. We should feel good about celebrating what these cars are and not keep trying to make them out to be something that they are not. :biggrin:

Reread the first post, Dave. It seems a lot of folks in the discussion before and after this thread began that are in no position to claim the "high road" here.

 

[eledille]

I don't find this result surprising or disappointing:

Model	Power	Torque	Weight	Power/weight	Torque/weight
M5	418 kW	680 Nm	1945 kg	215 W/kg	0.35 Nm/kg
MSP	310 kW	600 Nm	2108 kg	147 W/kg	0.28 Nm/kg

The M5 has 46% more power to weight at max power and 25% more torque to weight, so if both cars handle well and the M5 driver can keep the engine in the right gear most of the time, then there's no way an MSP can beat an M5 on the track.

A race track almost completely cancels all of the MSP's advantages, including low noise level, fuel economy, max torque at 0 rpm and "always in the right gear". These are real advantages on the road.

The MSP wasn't built for maximum performance - just look under the hood, there's a huge empty space there. If Tesla had filled that space with batteries and electronics, the MSP could have been faster. If it turns out that MSP does not perform as well as it should on the track given its power to weight ratio, then that would be mildly disappointing, but I would still consider it by far the best car. I would much rather have an MSP for driving and a KZ2 kart for racing than an M5.

 

[chrisn]

The M5 has 46% more power to weight at max power and 25% more torque to weight, so if both cars handle well and the M5 driver can keep the engine in the right gear most of the time, then there's no way an MSP can beat an M5 on the track.

In addition, the MSP doesn't (per Cottonwood's testing) seem to be able to sustain its power output for long under full load / track day circumstances. It is unclear why, but thermal limits is an obvious suspect. I actually think that some of MSPs advantages (low CG, flat TQ, instant response) DO translate to better lap times versus an ICE with comparable power/weight stats.

 

[Zextraterrestrial]

Throw in some liquid N and see what the S can do
'Overclock' the baby a little

 

[Brian H]

Wonder how the upcoming "Handling Package" will affect these stats and stand-offs!

 

[eledille]

In addition, the MSP doesn't (per Cottonwood's testing) seem to be able to sustain its power output for long under full load / track day circumstances.

Yes, I saw that. I'm also bit surprised considering it's liquid cooled. Does the battery have a dedicated coolant circuit? The problem might be that the motor and inverter heats the battery too much. It's hard to get rid of the heat if you have to keep temps below 50 degrees C or so.

I actually think that some of MSPs advantages (low CG, flat TQ, instant response) DO translate to better lap times versus an ICE with comparable power/weight stats.

I completely agree, I just don't think the advantages are anywhere near as large as 46% more power - on the track . On the road I think they are so large that I wouldn't even consider the M5 if I could choose between them.

 

[jerry33]

Yes, I saw that. I'm also bit surprised considering it's liquid cooled. Does the battery have a dedicated coolant circuit?

Yes, and it's own heat exchanger.

 

[CapitalistOppressor]

Been super busy lately with the election and with work, so haven't been able to keep fully abrest of the info stream.

Current summary -

Cottonwood had a bad day, and couldn't get a single valid lap in. That's an issue, which is either particular to Cottonwood, or a limitation with the car itself.

Personally I think it was Cottonwood centric, but that is pure opinion, based on the following - MSP has now been extensively track tested, by multiple publications and independant writers as a part of the review process. Lap times have not been released, but nobody has reported a problem with the car being unable to complete laps. Automobile Magazine reported the following -

For all its high-tech novelty, the Model S does an exceptional job at the things we expect any high-priced sport sedan to do well. The electric power steering is nuanced and well-weighted, with natural buildup just off-center. Through corners, the Model S exhibits impressive body control and vacuumlike grip despite weighing more than 4500 pounds. Editors also raved about the suspension's ability to soak up bumps that tortured other test cars. It was just as impressive on the racetrack -- yes, we took it on the track. "All that speed, along with powerful braking, superflat handling, and sharp steering, gives you the sense that you're invincible," marvels Jennings.

You'd think that at some point they'd mention that the car failed to complete a lap. For background, I've met Jean Jennings. She is not a professional race car driver, but she came up through Chrysler where she was a professional test driver and mechanic at their test facility. She is very experienced at pushing a car to it's limits. Among her testers at Automobile Magazine are also drivers with professional racing experience.

MotorTrend does extensive track testing with SCCA certified testers. Sports Car Club of America sanctions road racing, rallying and autocross, for both amateur and professional racers, and I would presume that their certified testers are accustomed to measuring performance at the edge of the envelope.

Neither magazine reported problems with the car being unable to complete a lap. Both raved about it's track performance (but did not publish lap times). Both publications voted it Car of the Year because of it's performance.

Edmunds Inside Line *DID* report a falloff in straight line 0-60 performance over multiple tests, with a best of ~4.3 and eventually falling off to ~4.6. This was on a hot day, and we speculated that it might be due to heat buildup. Nobody else has reported this, but the other publications only report best times.

Edmunds itself speculated it might be because of a falling battery charge, but seemed unconvinced. Every car made has a couple of tics variation on any given run. While this is not usually a linear decrease (or increase), in any limited set of runs (in this case 3) there is a significant chance you will have what appears to be a linear decrease in performance. More testing is required before we know there is an issue, let alone determining a cause.

At the 2012 Refuel races, a pre production Model S did a 1:51. At the time I posted that M5 does 1:40's and that a 1:51 is disappointing. But based on data from Inside line I was (and still am) convinced that MSP should be able to do 1:40's at Laguna Seca. We now have more test data which points to substantially faster times than 1:51's, but that and $8 will buy you a $6 burger combo at Carl's Jr (time to change the name of that burger IMHO).

Regardless, Cottonwood *DID* have a problem. Suggested reasons are -

A low state of charge causing excessive heat.
A malfunction in the cooling system.
A design limitation that prevents the car from being operated at maximum performance for even a single lap (I'll take odds against that).
?
I'll go out on a limb and propose another possibility pulled directly from my nether regions. It's known (or assumed) that Model S will cut power when it encounters heat issues, just like the Roadster. But it has been reported by Cinergi that the Model S will cut power output in the way described when its predicted range gets down to ~30 miles.

Under track conditions ~100 ideal miles might have briefly dipped under this limit as the car looked at actual usage and predicted that it could only make it ~30 miles under those conditions, causing it to cut power. Of course, once you stop pushing it the predicted range starts moving back up to the ideal range and suddenly you get your performance back until you try pushing again.

Call it the Top Gear rule. A 200+ mile Roadster predicts it can only go ~50 miles under load. If control software shuts you down at 30 miles predicted that might be an issue when you are racing with only 100 ideal miles left in the tank. Keep in mind, if you start with a full SOC you can race for dozens of real miles before this issue crops up.

Here is the link to Cinergi's report -

Behavior when getting low on range

Personally, I'd bet on any hypothesis not relying on a design limitation which causes the more advanced liquid cooled power electronics to shut down before the air cooled Roadster does. On a cool day.

I think that the firmware reigning in the car as reported by Cinergi (which I guess *IS* a design issue, albiet software related), or a simple mechanical malfunction in the cooling system are the most likely possibilities in the absense of additional data.

Edit:

Note Post #5 on Cinergi's report about the dotted yellow line at 160kWh (normally 320kWh) starting at 30 miles projected range.

Also note Cottonwoods report of the car being limited to 160kWh in post #1

Model S vs Roadster on the Track

With its liquid-cooled PEM, batteries, and motor, I had high hopes for the MSP to hold power. Unfortunately, my hopes were dashed. In 1/2 to 2/3 of the 1.83 mile lap, the little dashed limit line came on the power display, usually reducing power from 320 kW to a little more than 160kW. This shows up in the MSP having a better maximum speed (at the end of the south straight away) before the power was limited, but having worse lap times because of the reduced power in the last 1/3 of the lap. The Roadster tells you the PEM hot is the limiting factor. The MSP just lets you know the power is limited. We don't know if it was the PEM, batteries, or the motor. We did do this at the end of the day with the MSP charge at 100 miles or so rated range.

The lowest I've gone now is 20 miles left. The battery goes yellow around 30 and power is limited. I know others have had less. Would love to document what happens as you get to 0 ... can you keep driving all the way to 0? Past 0? Does power get limited even more as you get closer to 0? Details / pics please! Here's one to start:

View attachment 11616

The only thing unusual in those pics is the yellow dotted line near the 160kW power mark. That appeared with around 30 miles left.

 

[Zextraterrestrial]

You'd probably have the car floored for at least 1 minute of the 1:40-51? lap. which is pulling 310 kW and giving something like a 15-18 mile range (at a full range charge)
assuming a 300 mile range at 15.58 kW - um, if my math is proper