New Roadster Sport owner: questions

[ScottW]

Hi all -- I just became the proud owner of a radiant red 2010 Roadster Sport last week. Been having a blast driving it, and a couple questions have come to mind.

Today, I drove 45 miles each way, 90 miles round trip, on a drive. Mostly highway. I drove "spirited" with a few full power jaunts, but not crazy. When I returned home, I had about 15 miles (25 or so ideal) remaining in standard mode. Is this normal? I didn't drive too crazy -- I did drive at around 75-80mph on the freeway, but was surprised by the range.

Other question: I had the sport suspension set to 2 rear 1 front and found it to be too bouncy, and unstable around corners, so I had them firm it up, but they set it to 9 rear 8 front. It feels good on good roads, but on any freeway that's a bit uneven, it's a wild ride. Anyone have an "ideal" setting recommendation in this regard?

Feel free to point me to other threads if these have been discussed at length... Thanks.

 

[meloccom]

Welcome Scott,
I am still waiting for Tesla to come to where I live so I don't have a Roadster.
However, I think I can partially answer your questions.
Range at 75 - 80 MPH.
What is killing you on your trip (mostly) was your average speed.
Roadster Efficiency and Range
The above link will take you to a Tesla Motors blog that shows that your Roadster uses 350 Wh\Mile at 80 MPH versus 250Wh\Mile at 60 Mph. So a third more for the extra 20 Mph.
Also remember that Standard mode hides the Top and bottom 10% of charge to prolong the life of your battery. If you switch to Range mode you will suddenly have more 'Ideal miles'.
Adjusting the Adjustable Suspension
There is a whole thread on this Forum about adjusting the adjustable suspension and you will find it here:
Adjusting The adjustable Suspension
Good luck and enjoy your new roadster.

 

[DRM]

Welcome Scott!

I've had my 2010 (non-sport) for almost a year now. 105 (90+15) miles seems a bit low, even with "spirited" driving, but it isn't unheard of. At least for my car, a typical "standard mode" charge without topping off is about 186 ideal-miles. With my mostly-freeway commute, I average about 150 actual miles per charge, but YMMV.

The range thing takes a little bit of time to get used to, but after a couple weeks it really became a non-issue for me. Enjoy your new ride!

dan.

 

[dpeilow]

DRM - when you say "average" 150 miles, at what typical speed and what are the min and max on that average range? What causes it to vary?

Do you use the cruise control?

 

[scott451]

Hi all -- I just became the proud owner of a radiant red 2010 Roadster Sport last week. Been having a blast driving it, and a couple questions have come to mind.

Today, I drove 45 miles each way, 90 miles round trip, on a drive. Mostly highway. I drove "spirited" with a few full power jaunts, but not crazy. When I returned home, I had about 15 miles (25 or so ideal) remaining in standard mode. Is this normal? I didn't drive too crazy -- I did drive at around 75-80mph on the freeway, but was surprised by the range.

The next time you do a full charge in standard mode, "reset" the trip computer on the VDS screen. Drive "spirited" until you've gone 90+ miles. The trip computer will tell you the total Whrs/Mile. Recharge the car in standard and reset the trip computer again. Take another drive and set the cruse control to 65mph. after 90+ miles, check the trip computer for the Whrs/mile.

YMMV, but I've driven 182 miles at 65mph and got about 260Whrs/mile on a fulll charge in range mode.

-Scott

 

[Roger Reid]

Scott

I am trying autocross on my sport. I have found that setting the front sway bar to the softest (outside hole) and the rear to the firmest (inside hole) to work the best. I also set my rear shocks to 9 (firm) and the front to 5.

With these settings and traction control off, I start turns with a small amount of understeer then balance the steering with the throttle. It takes full throttle to induce oversteer and once oversteer is induced, you only have to back off a little to balance the car then back on full power. If you forget to turn off the traction control there is no way (in my experience) to break the rear tires loose (oversteer) on dry pavement.

Good luck with your settings.

Roger

 

[DRM]

DRM - when you say "average" 150 miles, at what typical speed and what are the min and max on that average range? What causes it to vary?

Do you use the cruise control?

This is just an observation, and not an actual measurement. It's based on my typical daily commute, a ~186mile charge in the morning, and estimated "real" miles left when I get home. I drive a mix of freeway and side streets.

 

[dpeilow]

This is just an observation, and not an actual measurement. It's based on my typical daily commute, a ~186mile charge in the morning, and estimated "real" miles left when I get home. I drive a mix of freeway and side streets.

Fair enough - just interested to get some real-world observations. Just from over here I'm not sure if freeway driving is mostly 65 or 75, etc. I'm told the cruise control makes a better job of hypermiling than most humans too.

 

[PopSmith]

I'm told the cruise control makes a better job of hypermiling than most humans too.

That sounds correct to me. Any car, no matter what it's powered by, is much more efficient at a constant rate of speed than when it is speeding up and slowing down, especially on the highway.

Combine the use of cruise control with some safe drafting and I believe you could see a nice range "boost" while driving.

 

[Lancelac]

I usually think of mileage in terms percentage of ideal miles. I'm a bit surprised to see your actual miles come out so low. You were getting about 105 miles out of 190, or about 55% going 75-80mph. I can say from experience that I get about 65-70% at that speed and have to average 90mph to get down to 55%. Admittedly, I only get about 65% around town, since I constant floor it for a few seconds at almost every opportunity.

 

[SByer]

That sounds correct to me. Any car, no matter what it's powered by, is much more efficient at a constant rate of speed than when it is speeding up and slowing down, especially on the highway.

I'd love to see MythBusters test this, as the myth among Prius owners is that speeding up and coasting increases mileage (PIA even echoed this myth in a blog post where they liked the Leaf having regen not on the accelerator pedal). I suspect it's really because they end up at an overall lower speed. An ICE is so inefficient, however, that it's not inconceivable that it would work.

For an EV, however, I'm pretty darned sure cruise control wins any day of the week.

Oh, and regen on the accelerator pedal is a big, big win - especially for commuting!

 

[ChadS]

I never tried pulse-n-glide in my Prius, mostly just because there's too much traffic around here and I don't want to get in the way. But I've seen enough numbers that, while initially skeptical, I do believe it works in some scenarios.

It is clear that less energy is required to push an object at a set speed than to speed up and slow down while maintaining the same average speed. However, you also have to consider the efficiency of getting that energy. Gas engines (more so than electric motors, less so than turbines) have definite "sweet spots" where they are more efficient than others. If you can have the engine off while coasting, and generating in a sweet spot while on, you may (not always!) be able to do better than keeping the engine on all the time in a less-efficient spot.

While this is probably harder to do with a more-efficient and less peaky electric motor, it is still probably possible. For example, look at Tesla's engineering blog that shows MPC at different speeds. It gets steadily lower at higher speeds as you'd expect due to resistance. But it also gets sharply lower below 18mph; there must be some drag in the system (I've heard this inflection point is MUCH lower in a Mini-E, more like 3mph; I'm not sure what's causing this in the Tesla), so if you were at really low speeds, pulse-n-glide could be more efficient than holding a steady speed.

Incidentally, that PIA blog was by Marc Geller, who has hypermiled for years in electric cars. He and I were discussing this topic while he was driving my Tesla when I was down in San Francisco; this was about the only thing we didn't agree on. He's still a big fan of coasting and doesn't like regen on the accelerator; I like it for several reasons, including the fact that you CAN still coast--you just have to hold the pedal in the right spot. There's always the Neutral button as well.

 

[Palpatine]

As an owner of two Prius vehicles and a Tesla owner, I feel qualified to chime in here. My 2005 Prius is non-modified and my 2009 Prius has the Hymotion Plug-In upgrade.

The Prius has a definite sweet spot at 38-40 mph on cruise control. When the car is fully warmed up, it will turn off the engine and be able to maintain that speed in electric mode for significant periods of time.

Even a non-modified Prius can experience this. Getting significant miles at 99.9 mpg is key to boosting your average.

But if you were to drive at 42 mph on cruise control, the software kills this trick. It automatically has the ICE turned on at any speed above 41 mpg.

So the most efficient speed in a Prius has nothing to do with the efficiencies of the ICE. It is software related.

 

[William3]

Incidentally, that PIA blog was by Marc Geller, who has hypermiled for years in electric cars. He and I were discussing this topic while he was driving my Tesla when I was down in San Francisco; this was about the only thing we didn't agree on. He's still a big fan of coasting and doesn't like regen on the accelerator; I like it for several reasons, including the fact that you CAN still coast--you just have to hold the pedal in the right spot. There's always the Neutral button as well.

In your Tesla Roadster, can you switch from Neutral to Drive without your foot on the brake pedal? I don't seem to be able to in my 2010.

 

[bolosky]

In your Tesla Roadster, can you switch from Neutral to Drive without your foot on the brake pedal? I don't seem to be able to in my 2010.

I tried it on my 2010, and I can switch between neutral and drive without using the brake if I'm moving, but I need to apply the brake if I'm stopped.

 

[doug]

I tried it on my 2010, and I can switch between neutral and drive without using the brake if I'm moving, but I need to apply the brake if I'm stopped.

How about drive and reverse?

 

[Bradleybang]

Yes, drive from reverse.

Done many a time out of driveway but there is a speed/software failure setup.

If going over a certain backward speed and you touch drive, a warning comes on and says you must touch brake to switch gears.

The speed is low under 4mph.