Posted by Bruce Richmond on January 19, 2011, 5:31 am
> On 1/18/2011 10:17 PM, Bruce Richmond wrote:
> >> On 1/18/2011 7:40 AM, Bruce Richmond wrote:
> >>>> On 1/18/2011 1:13 AM, Bruce Richmond wrote:
> >>>>>> On 12/31/2010 3:09 PM, Neo wrote:
> >>>>>>>> On 12/31/2010 1:52 PM, Neo wrote:
> >>>>>>>>>> On 12/29/2010 4:40 AM, Neo wrote:
> >>>>>>>>>>> Hypermiling in cold weather
> >>>>>>>>>>> ----------------------------------------
> >>>>>>>>>>> The local ambient driving temperature has dropped to a range
> >>>>>>>>>>> somewhere beteen 37 Fahrenheit to 27 Fahrenheit with the
> >>>>>>>>>>> average about 32 Fahrenheit. I've increased the tire pressure
> >>>>>>>>>>> to about 48 psi front and 45 psi rear on the Yokohama Avid
> >>>>>>>>>>> S33. The ride is very taut
> >>>>>>>>>> Good luck on snow and ice with those tires and pressures.
> >>>>>>>>> Yokohama Avid S33 Tires at these higher
> >>>>>>>>> air pressures do not appear to have any additional
> >>>>>>>>> tendency to hydroplane.
> >>>>>>>> You won't be hydroplaning on snow and ice, skippy.
> >>>>>>>> You will be skating.-
> >>>>>>> Yes.
> >>>>>>> The Yokohama Avid S33 Tires are designed for
> >>>>>>> only light snow - they have only fair snow and
> >>>>>>> ice traction performance.
> >>>>>> And worse to none at those tire pressures.- Hide quoted text -
> >>>>>> - Show quoted text -
> >>>>> And you are talking out of your ass if you think the higher pressures
> >>>>> have much effect on traction in the snow. I have been getting around
> >>>>> just fine in the snow here in NH.
> >>>> You are deluded if you think snow and ice traction are unaffected by
> >>>> tire pressure. Make sure you note it in your next accident report, and
> >>>> pay up on contributory negligence.- Hide quoted text -
> >>>> - Show quoted text -
> >>> I didn't say it had no effect, I said it doesn't have much affect.
> >>> How much more flex do you think 35 psi provides? What exactly do you
> >>> think causes 35 psi to provide more traction? If you don't answer
> >>> you
> >>> will have shown that you don't know what you are talking about.
> >> Tire footprint and optimization with suspension dynamics.- Hide quoted text -
> >> - Show quoted text -
> > Footprint is correct. The rest is grasping at straws. Now how much
> > do you think the footprint changes when going from 35 to 45 psi? I
> > think we can agree that you would be hard pressed to tell the
> > difference by just looking at it. When you see a tire and think "soft
> > tire" it is usually in the low 20s if not lower.
> > Now let me ask you, do you run the latest sticky sport compound tires
> > on your car? No?! Why not? Could it be because they are expensive
> > and wear out quickly? IOW you are passing up the option of having
> > higher cornering limits and shorter braking distances to save a few
> > bucks. To quote you, "Make sure you note it in your next accident
> > report, and pay up on contributory negligence."
> > Many people run all season tires year round rather than switch back
> > and forth between summers and snows. They don't provide the traction
> > of snows, but they are willing to accept that compromise based on the
> > mix of driving conditions they expect to encounter. Inflating your
> > tires to the high side of the stock specs is no different. It is a
> > trade off we are allowed to make. And again, the effects are
> > minimal. I drove home on snow covered roads again today with no
> > problems.
> Good luck. Suit yourself. The contact patch changes dramatically with
> inflation pressure as well as suspension loading, camber, roll steer. I
> would expect this to be particularly so for low rolling resistance tires.
> Perhaps you should ask someone at Toyota what they think of your street
> driving experimentation. Better yet, ask a product liability attorney.
> Yes, I do run soft compounds on the sports car, and I have dialed in the
> proper pressures for a variety of road surfaces and events. None of
> them on the street.
> Yes, I do use separate sets of high performance and winter snows for
> each street vehicle. Properly inflated.
> Better dial up that attorney.- Hide quoted text -
> - Show quoted text -
LOL, Sure you do, In your dreams. Ha Ha
Posted by News on January 19, 2011, 11:38 am
On 1/19/2011 12:31 AM, Bruce Richmond wrote:
>> On 1/18/2011 10:17 PM, Bruce Richmond wrote:
>>
>>
>>
>>
>>
>>>> On 1/18/2011 7:40 AM, Bruce Richmond wrote:
>>
>>>>>> On 1/18/2011 1:13 AM, Bruce Richmond wrote:
>>
>>>>>>>> On 12/31/2010 3:09 PM, Neo wrote:
>>
>>>>>>>>>> On 12/31/2010 1:52 PM, Neo wrote:
>>
>>>>>>>>>>>> On 12/29/2010 4:40 AM, Neo wrote:
>>
>>>>>>>>>>>>> Hypermiling in cold weather
>>>>>>>>>>>>> ----------------------------------------
>>
>>>>>>>>>>>>> The local ambient driving temperature has dropped to a range
>>>>>>>>>>>>> somewhere beteen 37 Fahrenheit to 27 Fahrenheit with the
>>>>>>>>>>>>> average about 32 Fahrenheit. I've increased the tire pressure
>>>>>>>>>>>>> to about 48 psi front and 45 psi rear on the Yokohama Avid
>>>>>>>>>>>>> S33. The ride is very taut
>>
>>>>>>>>>>>> Good luck on snow and ice with those tires and pressures.
>>
>>>>>>>>>>> Yokohama Avid S33 Tires at these higher
>>>>>>>>>>> air pressures do not appear to have any additional
>>>>>>>>>>> tendency to hydroplane.
>>
>>>>>>>>>> You won't be hydroplaning on snow and ice, skippy.
>>
>>>>>>>>>> You will be skating.-
>>
>>>>>>>>> Yes.
>>
>>>>>>>>> The Yokohama Avid S33 Tires are designed for
>>>>>>>>> only light snow - they have only fair snow and
>>>>>>>>> ice traction performance.
>>
>>>>>>>> And worse to none at those tire pressures.- Hide quoted text -
>>
>>>>>>>> - Show quoted text -
>>
>>>>>>> And you are talking out of your ass if you think the higher pressures
>>>>>>> have much effect on traction in the snow. I have been getting around
>>>>>>> just fine in the snow here in NH.
>>
>>>>>> You are deluded if you think snow and ice traction are unaffected by
>>>>>> tire pressure. Make sure you note it in your next accident report, and
>>>>>> pay up on contributory negligence.- Hide quoted text -
>>
>>>>>> - Show quoted text -
>>
>>>>> I didn't say it had no effect, I said it doesn't have much affect.
>>>>> How much more flex do you think 35 psi provides? What exactly do you
>>>>> think causes 35 psi to provide more traction? If you don't answer
>>>>> you
>>>>> will have shown that you don't know what you are talking about.
>>
>>>> Tire footprint and optimization with suspension dynamics.- Hide quoted text
-
>>
>>>> - Show quoted text -
>>
>>> Footprint is correct. The rest is grasping at straws. Now how much
>>> do you think the footprint changes when going from 35 to 45 psi? I
>>> think we can agree that you would be hard pressed to tell the
>>> difference by just looking at it. When you see a tire and think "soft
>>> tire" it is usually in the low 20s if not lower.
>>
>>> Now let me ask you, do you run the latest sticky sport compound tires
>>> on your car? No?! Why not? Could it be because they are expensive
>>> and wear out quickly? IOW you are passing up the option of having
>>> higher cornering limits and shorter braking distances to save a few
>>> bucks. To quote you, "Make sure you note it in your next accident
>>> report, and pay up on contributory negligence."
>>
>>> Many people run all season tires year round rather than switch back
>>> and forth between summers and snows. They don't provide the traction
>>> of snows, but they are willing to accept that compromise based on the
>>> mix of driving conditions they expect to encounter. Inflating your
>>> tires to the high side of the stock specs is no different. It is a
>>> trade off we are allowed to make. And again, the effects are
>>> minimal. I drove home on snow covered roads again today with no
>>> problems.
>>
>> Good luck. Suit yourself. The contact patch changes dramatically with
>> inflation pressure as well as suspension loading, camber, roll steer. I
>> would expect this to be particularly so for low rolling resistance tires.
>>
>> Perhaps you should ask someone at Toyota what they think of your street
>> driving experimentation. Better yet, ask a product liability attorney.
>>
>> Yes, I do run soft compounds on the sports car, and I have dialed in the
>> proper pressures for a variety of road surfaces and events. None of
>> them on the street.
>>
>> Yes, I do use separate sets of high performance and winter snows for
>> each street vehicle. Properly inflated.
>>
>> Better dial up that attorney.- Hide quoted text -
>>
>> - Show quoted text -
> LOL, Sure you do, In your dreams. Ha Ha
Laugh it up. Remember to drive it all the way through the crash.
Posted by Elmo P. Shagnasty on December 29, 2010, 12:51 pm
In article
> Because using the heater would lessen the Prius's fuel
> efficiency, I am not using cabin heat - which makes driving
> in this weather - a very cold situation.
You're screwing yourself on this one.
The traction batteries are vented to the passenger cabin, because they
are designed to work best in the same environment as what's comfortable
for the passengers.
Leaving the AC and heat off is WORSE for the traction batteries.
Posted by Neo on December 31, 2010, 7:05 pm
wrote:
> In article
> > Because using the heater would lessen the Prius's fuel
> > efficiency, I am not using cabin heat - which makes driving
> > in this weather - a very cold situation.
> You're screwing yourself on this one.
> The traction batteries are vented to the passenger cabin, because they
> are designed to work best in the same environment as what's comfortable
> for the passengers.
> Leaving the AC and heat off is WORSE for the traction batteries.
Good Point- The Prius HV Traction battery does have an optimum
operating temperature and it is cooled/heated by the
air drawn from the passenger cabin. Heat can prematurely wear
out or destroy the Prius HV Traction battery. Cold can reduce the
HV Traction Battery's output capacity. The conditioned air from
the passenger cabin is part of the Prius's battery thermal management
system. The Prius HV battery is suppose to operate between
5 C (41 F) degrees to 45 C ( 113 F) degrees with the optimum
temperature of 25 C degrees (77 F). I now have a new reason
to heat and cool the passenger cabin.
http://www.nrel.gov/vehiclesandfuels/energystorage/pdfs/2a_2002_01_1962.pdf
Posted by Neo on January 13, 2011, 3:00 am
Tire Pressure
==========
As some have predicted, I've finally experienced
some lost of tire tractrion from the increased tire
pressures at 48 psi front and 46 psi rear using
Yokohama Avid S33 all season tires that come standard
with the 2010 Toyota Prius III. When attempting to
go from 35 mph to 0 mph on a wet 10 degrees downhill
grade on an asphalt road - the loss of traction added
approximately about 20 feet more to the stopping
distance. Because I normally start slowing down and
braking early ( to maximize energy recovery
via the regenerative brakes) I noticed the loss in
braking performance early and I was able to easily
compensate for the loss of performance. Sadly the
48/46 psi tire setting has not provide any noticeable
fuel efficiency improvement than the 44/42 psi
setting. I have since reset the tire pressures
back to 44/42 psi setting which in the past improved
fuel efficiency but still provided adequate level
of performance wrt to braking and handling in
urban/suburban driving environments..
Grill Blocking
============
The 100% grill blocking has reduced the number of
times the Prius turns on the ICE to keep the catalytic
converter/emissions system warm. Sofar the coolant
temperature has stay more or less under 181
Fahrenheit degrees in mainly urban driving. For the
winter, grill blocking has been a significant factor in
keeping the FE up. More effective than grill blocking
is to just to drive when the temperature is warmer,
e.g. drive in the afternoon instead of at night.
2010 Toyota Prius III, Blue Ribbon/Dark Grey, OEM floormats
Yokohama Avid S22 (front 44 psi, rear 42 psi)
ScangaugeII ( RPM, MPG/AVG, FWT, GPH)
lower grill 100% blocked, upper grill 100% blocked
DC/MD/VA metro area
odeometer = +7500 miles
XML site map
> >> On 1/18/2011 7:40 AM, Bruce Richmond wrote:
> >>>> On 1/18/2011 1:13 AM, Bruce Richmond wrote:
> >>>>>> On 12/31/2010 3:09 PM, Neo wrote:
> >>>>>>>> On 12/31/2010 1:52 PM, Neo wrote:
> >>>>>>>>>> On 12/29/2010 4:40 AM, Neo wrote:
> >>>>>>>>>>> Hypermiling in cold weather
> >>>>>>>>>>> ----------------------------------------
> >>>>>>>>>>> The local ambient driving temperature has dropped to a range
> >>>>>>>>>>> somewhere beteen 37 Fahrenheit to 27 Fahrenheit with the
> >>>>>>>>>>> average about 32 Fahrenheit. I've increased the tire pressure
> >>>>>>>>>>> to about 48 psi front and 45 psi rear on the Yokohama Avid
> >>>>>>>>>>> S33. The ride is very taut
> >>>>>>>>>> Good luck on snow and ice with those tires and pressures.
> >>>>>>>>> Yokohama Avid S33 Tires at these higher
> >>>>>>>>> air pressures do not appear to have any additional
> >>>>>>>>> tendency to hydroplane.
> >>>>>>>> You won't be hydroplaning on snow and ice, skippy.
> >>>>>>>> You will be skating.-
> >>>>>>> Yes.
> >>>>>>> The Yokohama Avid S33 Tires are designed for
> >>>>>>> only light snow - they have only fair snow and
> >>>>>>> ice traction performance.
> >>>>>> And worse to none at those tire pressures.- Hide quoted text -
> >>>>>> - Show quoted text -
> >>>>> And you are talking out of your ass if you think the higher pressures
> >>>>> have much effect on traction in the snow. I have been getting around
> >>>>> just fine in the snow here in NH.
> >>>> You are deluded if you think snow and ice traction are unaffected by
> >>>> tire pressure. Make sure you note it in your next accident report, and
> >>>> pay up on contributory negligence.- Hide quoted text -
> >>>> - Show quoted text -
> >>> I didn't say it had no effect, I said it doesn't have much affect.
> >>> How much more flex do you think 35 psi provides? What exactly do you
> >>> think causes 35 psi to provide more traction? If you don't answer
> >>> you
> >>> will have shown that you don't know what you are talking about.
> >> Tire footprint and optimization with suspension dynamics.- Hide quoted text -
> >> - Show quoted text -
> > Footprint is correct. The rest is grasping at straws. Now how much
> > do you think the footprint changes when going from 35 to 45 psi? I
> > think we can agree that you would be hard pressed to tell the
> > difference by just looking at it. When you see a tire and think "soft
> > tire" it is usually in the low 20s if not lower.
> > Now let me ask you, do you run the latest sticky sport compound tires
> > on your car? No?! Why not? Could it be because they are expensive
> > and wear out quickly? IOW you are passing up the option of having
> > higher cornering limits and shorter braking distances to save a few
> > bucks. To quote you, "Make sure you note it in your next accident
> > report, and pay up on contributory negligence."
> > Many people run all season tires year round rather than switch back
> > and forth between summers and snows. They don't provide the traction
> > of snows, but they are willing to accept that compromise based on the
> > mix of driving conditions they expect to encounter. Inflating your
> > tires to the high side of the stock specs is no different. It is a
> > trade off we are allowed to make. And again, the effects are
> > minimal. I drove home on snow covered roads again today with no
> > problems.
> Good luck. Suit yourself. The contact patch changes dramatically with
> inflation pressure as well as suspension loading, camber, roll steer. I
> would expect this to be particularly so for low rolling resistance tires.
> Perhaps you should ask someone at Toyota what they think of your street
> driving experimentation. Better yet, ask a product liability attorney.
> Yes, I do run soft compounds on the sports car, and I have dialed in the
> proper pressures for a variety of road surfaces and events. None of
> them on the street.
> Yes, I do use separate sets of high performance and winter snows for
> each street vehicle. Properly inflated.
> Better dial up that attorney.- Hide quoted text -
> - Show quoted text -