Featured Lexus RZ is selling $13,000 below MSRP in Southern California due to inventory surplus

Heard the cherry farm needs some help

LFP to another Li-ion chemistry isn't apples to apples, but BEV, with a battery designed for energy content, to hybrid, with an engine and battery designed for power delivery is?

After moving those goal posts, you had to narrow the comparison down to city ratings, cause the loss in combined mpg for the Prius is over 5%. Then for the more efficient Prius trim, the city advantage over the Model Y is just 0.84%.

 

that's a crabapple to apple comparison - difference being Toyota's smaller battery - shorter range. The lighter weight makes the difference.

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I would say lime to tomato, but who is counting. The goal line has been changed so many times, I have no idea what it is, but prius is a car so why not compare it at least the faster, bigger, heavier model 3 instead of the model Y.

Compare Side-by-Side



In city efficiency the model 3 drops from 140 mpge rwd to 137 mpge awd, while the prius drops from 57 mpg to 53 mpg. They seem like comparable drops but the tesla drops less both in absolute and even more in percentage terms. The prius actually is more efficient in the city than the highway, but that is because unlike the tesla, the prius must use a less efficient range of the engine, while the tesla not burdened by that does better in the city. Is 124 mpge on the highway better or worse than 56 mpg in the prius, ymmv. The awd tesla in this case takes a bigger hit on weight and rolling resistance since it has a larger heavier battery and a heavier motor/transmission on the other axle.

 

It is a RZ thread.

The rear motor of the Prius not even being half the power of the one in the RZ or bZ4X means a similarly reduced eddy current effect.

If using a gasoline engine doesn't matter, then neither does a different battery chemistry.

 

its rear motor output is maybe a third of the front one in the Y, and the heavier SUV bests it in efficiency loss for AWD. It does less than 1% better looking only at city ratings.

Electric motors don't pay as steep an efficiency cost to get performance as ICE do.

Most AWD systems on personal cars are asymetrical, with the secondary axle drive off until needed. I haven't seen anything to state that isn't the case for EVs.

The bZ4X AWD uses a less powerful motor in the front, keeping the power between the it and the FWD near the same. The AWD efficiency loss for it is only 2.5% better than the RZ sees.

 

Need some help with those goal posts?

Any evidence the different battery chemistries actually make a difference?

 

Just the cost of production. But such things are subject to market prices and the march of technology.

Bob Wilson

 

If anything, I figure the use of LFP in the RWD model would mean the weights of the two would be closer than if it was NCA.

 

The 2022 AWD was using 4680 cells and had 7.6kWh more capacity. Part of its reduced efficiency is in that 60 to 70 pounds. NCM to NCM wasn't going to completely variable free.

Overall, it seems to be a 154 pound difference between the LFP RWD and AWD. The NCM SR RWD might have been another 55 pounds lighter than the LFP, or about the difference between the AWD and LR AWD. Comparing those two ratings, the NCM RWD might have been 2 mpge in the city. Or maybe not, as the posted fuel economy of the 2021 Standard Range RWD Model y is the same as the later, presumably LFP models.

 

But when tesla uses LFP its been in the lighter car with a smaller pack.

This may be true of Toyota, but doesn't make much sense when comparing teslas. The current US model Y rwd and awd both use NCA. They use the same pack. rwd aer is 320, awd is 310. You had used the model 3 with LFP in a smaller pack in the model 3 rwd and NCA in the larger pack for awd. Tesla changes battery types based on availability. The Y was to use the 4860, but production was only high enough for the cyber truck. I don't know what battery the model 3 awd is currently using, but it is not NCA built in north america. It could be nca, nmc, or lfp imported.

 

Part of the problem, yes, sort of, but not exactly.

Back in the day, cars tended to have a lot of weight bias between wheels under engine and wheels that weren't.

• The air cooled VW's were known for good now traction at slow speeds because they had a lot of weight over the drive wheels in comparison with the front wheels. But the greater weight over the rear wheels caused them to oversteer at higher speeds.
• Many FWD cars were the same ias the air cooled VW's but on the other end of the vehicle. They tended to understeer as a result

But modern day cars, not just EV's have much closer to 50/50 weight distributions than older cars. So the point that "more weight over the front and not over the drive wheels" is a rather moot point anymore. The result?

• ButEven with all it's traction control, modern snow tires and such, a car like my Avalon Hybrid still isn't as good at slow speeds in the snow as an old 1980's or 90's Camry or Corolla or similar FWD vehicle. It has a much closer to 50/50 weight distribution than those older cars.
• The weight is another factor. If you get stuck you have to call a tow truck. No pushing our modern day behemouths out of the snow bank like you could in an air cooled VW Beetle or a 1980's or 90's VW or Toyota or Mazda or Honda.
• On the other hand, my Avalon does have better control at higher speeds. An old Camry would want to just go straight. The Avalon can turn a bit better.
• By comparison, a RWD with slight rear bias, like a RWD Tesla, should have even better handling, at least for a professional driver. Many of the vehicles that I drove with greater weight in the rear had the advantage of drifting around corners. The rear would slide out, but at least you still had traction on your steering wheels, so as long as the rear didn't slide out too far and you knew how to properly countersteer you'd be ok. A lot of people don't understand how this works and think that oversteering on snow and ice is an instant accident waiting to happen, but the fact is you can generally turn tighter corners at higher speeds with oversteer than with 50/50 bias. More front bias and understeer are best for novices in my opinion as the understeer tends to correct itself with natural reactions, whereas you have to be very contientious to drive an oversteering vehicle.

But getting back to reality, a person shouldn't be driving fast on snow and ice anyway. If the road is snow covered you should never go faster than 2/3 the speed limit in any vehicle. And on ice that speed should be much slower. So all this near 50/50 or slight oversteer advantage becomes moot when you drive like I do now and realize that snow means slow. So, in the end, an old rear engine air cooled VW would be a better choice, and an old FWD with a lot of front bias would be even better. My 1985 VW Golf was impossible to get stuck.

 

BEVs are closer to the 50/50 weight distribution than most cars available today, with the motor over the drive wheels.

RWD is coming back in EVs for the performance advantage. ABS, traction control, and VSC are all mandatory now. These will control the downsides of RWD.

Virtually all the BEVs available have an AWD option for locations where better traction and control is needed. The few that don't are probably FWD. You can choose between FWD and RWD when buying one of the Blazer EV trims.

Transverse engines over the drive axle have lower drive train loses than transverse. Manufacturers went to FWD for that reason. They could have done rear engine, but didn't have the electronic nannies to help inexperienced drivers.

 

A RWD EV with a 50/50 weight distribution and modern traction control and such is still going to be worse in slow speed acceleration than an old FWD with a 60/40 weight distribution. The same as a modern day FWD. The Nissan Leaf was not near as good in the snow as the 1985 VW Golf it replaced. The Golf also could be fitted with snow chains, something that can't be done on many new cars.

To me the RWD performance advantage is fine but not worth anything to me personally.

If they made an AWD that truly is an economy car with an excelent reliability forcast, I'd be all for it. This is one reason I would consider a Subaru Impreza. But AWD EV anything is way too expensive.