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Interesting? We all are well aware of this I hope. I am a bit surprised they did not mention or get into Tire pressure. 48psi on our Volt all year gets us 60k out of em and 4% more AER, also it states in our Volt manual that 50 MPH is the most efficient speed on the freeway. I also doubt that the tires were specifically designed for the model s like our volt radials were.
 

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What's intersting is how their standard 19" tires are your run-of-mill GT tires, and the 21's typically use either Conti DW's or Michelin PSS and yet it's merely a 3% range impact.

For the added handling capability of the summer tires, that's really not that big of a hit.
 

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What's a couple dozen miles of range when you are getting 250+ with any 85 model S? I'll bet Ari C will find a way to get 300-400 miles of range if given the opportunity. Alas, the only Model S I would buy is the 60 as I just can't justify the high cost of the bigger battery. But alas, at this point, even considering an ELR for about half off MRSP vs. Tesla Model 60, the ELR is winning just by sheer lower discounted price. Maybe if the bottom falls out of the used Model S market, I may consider it.

I'm going to need some new tires eventually, what's the consensus on all season radials for the Volt?
 

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I think the stock Volt tires are terrible, so plan on switching to summer only tires in the spring. I made this decision when I noticed my winter tires handled better than my OEM tires :)

Granted, if you don't care about cornering, braking, etc then the stock tires are fine.

I like the comment that the first 1000 miles on new tires can be an additional 5% worse. This is closer to 8% worse on new tires, but should diminish down to 3% when the tires "break in". On the Volt this would be about 3 miles range new, down to about 1 mile range when they are broken in.
 

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Interesting? We all are well aware of this I hope. I am a bit surprised they did not mention or get into Tire pressure. 48psi on our Volt all year gets us 60k out of em and 4% more AER, also it states in our Volt manual that 50 MPH is the most efficient speed on the freeway. I also doubt that the tires were specifically designed for the model s like our volt radials were.
Well, what the manual actually says is:

Electric range is maximized at
80 km/h (50 mph) and below. Higher
speeds use more energy and can
significantly reduce electric range
 

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Well, what the manual actually says is:

Electric range is maximized at
80 km/h (50 mph) and below. Higher
speeds use more energy and can
significantly reduce electric range
The manual is a little misleading. Slower is always better when driving on battery (assuming no heater use etc.) until you get down to around 10-15 mph at which point it gets less efficient as you go slower. So, 20 mph is quite a bit more efficient than 50 mph.
 

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I switched to Continental PureContacts with Ecoplus (LRR) and I love them. MUCH improved dry and wet handling and pretty good in the snow too. Also quieter and range is the same.
What's a couple dozen miles of range when you are getting 250+ with any 85 model S? I'll bet Ari C will find a way to get 300-400 miles of range if given the opportunity. Alas, the only Model S I would buy is the 60 as I just can't justify the high cost of the bigger battery. But alas, at this point, even considering an ELR for about half off MRSP vs. Tesla Model 60, the ELR is winning just by sheer lower discounted price. Maybe if the bottom falls out of the used Model S market, I may consider it.

I'm going to need some new tires eventually, what's the consensus on all season radials for the Volt?
 

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The part I don't understand is that the trend on the P85D range - it acts as if the car has worse aerodynamics than the rest, which seems improbable. (though I know this isn't really the place to find answers.)
There's only aero, rolling resistance, and drive train efficiency. Given the cars are exactly the same shape and that rolling resistance is pretty constant, I'd think the differences would have to be attributed to drive train inefficiencies.
 

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There's only aero, rolling resistance, and drive train efficiency. Given the cars are exactly the same shape and that rolling resistance is pretty constant, I'd think the differences would have to be attributed to drive train inefficiencies.
That would make sense. My problem is that the Tesla data shows that the P85D is more efficient than the others at low speeds and less efficient at high speeds. The expected higher drivetrain losses should present like rolling resistance, and therefore be an even hit across the speed range I would think. So I very confused. :)
 

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There's only aero, rolling resistance, and drive train efficiency. Given the cars are exactly the same shape and that rolling resistance is pretty constant, I'd think the differences would have to be attributed to drive train inefficiencies.
If one car has the adjustable suspension and the other doesn't, that changes the aero despite the identical shape of the car. Weight also changes with the added dual motors.
 

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If one car has the adjustable suspension and the other doesn't, that changes the aero despite the identical shape of the car. Weight also changes with the added dual motors.
The P85D adds 291 pounds of weight, while the 85D adds 176 pounds.

The weight increase is greater with the P85D because the front motor is an addition to the existing rear motor, while the 85D reduces the size of the rear motor.

So the P85D is 6.26% heavier, while the estimated range loss at a flat, constant 75mph from 242 to 240 represent an increase in energy use of 0.83%. So it seems that as highway speed increases, the efficiency gains from the use of the smaller front motor drops, and the increased drag from having two motors, plus the additional rolling resistance from extra weight will makes it less efficient overall.
 

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Discussion Starter · #15 ·
What's a couple dozen miles of range when you are getting 250+ with any 85 model S? I'll bet Ari C will find a way to get 300-400 miles of range if given the opportunity. Alas, the only Model S I would buy is the 60 as I just can't justify the high cost of the bigger battery. But alas, at this point, even considering an ELR for about half off MRSP vs. Tesla Model 60, the ELR is winning just by sheer lower discounted price. Maybe if the bottom falls out of the used Model S market, I may consider it.

I'm going to need some new tires eventually, what's the consensus on all season radials for the Volt?
I like the Michelin Primacy MXV4s.... H speed rated is softer and a little bit better in the snow....
 
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