new prius test car spotted

[aerohead]

Originally Posted by Phase

its pretty extreme. im also surprised they are using bigger wheels which usually means worse fuel economy. sure it feels the wheel well but also increases rolling resistance and tire cost

the rear looks like a tesla model 3 rip off. i wonder what would happen if i extended my rear windshield like that and then did a little duckbill lip spoiler versus the big flat spoiler currently on my ioniq and the current prius

I suspect that no kind of spoiler will help the IONIQ. You're at a 'kamm' form already. Elongation of the entire tail is where the money would be. That's what 'Kamm' did.

[JSH]

We will find out next week. The reveal is 16-November

https://www.caranddriver.com/news/a4...ius-confirmed/

[aerohead]

According to whichcar.com.an./news/2023-toyota-prius
the new Prius has Cd 0.197 ( same as 1996 GM EV1 ).
It's 2-inches less in height.
No mention of frontal area, so, no CdA yet.

[Nathan jones]

Originally Posted by JSH

Larger diameter tires have lower rolling resistance than smaller diameter tires.

Web quote: Tires with a smaller diameter have a higher rolling resistance with the same inflation pressure, because tire deformation is proportionally greater. The tire is flattened more and is “less round”.

This is one of the reasons why giant wheels / tires are all the range on EVs. This is why BMW had special skinny 19" tires made for the i3.


However larger wheel / tire combos tend to be heavier which increases rotational mass and consumes more fuel when accelerating - which hurts city mileage. As with everything there are tradeoffs.

Not true, tires with a smaller diameter only have less contact area (resistance) if they are not inflated to a equal weight ratio pressure. Which if you were changing wheels is not something you would miss. In real driving enviroment the net efficiency of smaller lighter wheels is larger so as phase says swapping for smaller wheels whether highway or not is still more efficient

Also using a 5.5j/185mm tire on a regular car pumped up to low contact would have very low grip in wet conditions irrespective of the overall diameter

[Phase]

Originally Posted by Nathan jones

Not true, tires with a smaller diameter only have less contact area (resistance) if they are not inflated to a equal weight ratio pressure. Which if you were changing wheels is not something you would miss. In real driving enviroment the net efficiency of smaller lighter wheels is larger so as phase says swapping for smaller wheels whether highway or not is still more efficient

Also using a 5.5j/185mm tire on a regular car pumped up to low contact would have very low grip in wet conditions irrespective of the overall diameter

less wet grip when over inflated, but over inflated tires hydroplane less. fun fact. so pick your poison

[freebeard]

Not true, tires with a smaller diameter only have less contact area (resistance) if they are not inflated to a equal weight ratio pressure. Which if you were changing wheels is not something you would miss. In real driving enviroment the net efficiency of smaller lighter wheels is larger so as [P]hase says swapping for smaller wheels whether highway or not is still more efficient

What is a[n] equal weight ratio pressure?

The paradigm is a tall, narrow tire such that contact patch is equal, I don't know about the pressure.

The narrow tire will [or at least should] hydroplane less at simlar pressure.

Rubber and aluminum weigh about the same.

[Nathan jones]

Preferably the contact area is not to be a circle. Phase is still correct.

Aluminium is more than twice the density of rubber

Good luck guys

[freebeard]

Originally Posted by myself

What is a[n] equal weight ratio pressure?

My understading is that the contact patch is an oval. A short, wide tire has a contact patch that is wider than it is longer, good for cornering. A tall narrow tires contact patch is long and narrow, for less rolling resistance.

[rmay635703]

The Gen V announcement was more focused on power and looks and less focused on price and fuel economy.

The PHEV will net a longer range, not sure if I care at this point

[redpoint5]

I'm annoyed that Toyota didn't include a 16 kWh battery for the PHEV (Prime) from the beginning because they left federal tax money on the table wasting those credits on an 8.8 kWh battery.

The gen IV should have been what this generation is.

~40 mile EV range is quite good. With a 16 kWh battery (the one in the RAV4 Prime), it could have been closer to 60 miles of range.

That said, I have no idea where the federal subsidy is nowadays. Did the new one supersede the previous one? If so, my understanding is all manufacturers that meet a certain percent of domestic manufacturing and/or assembly now qualify.