EV or no EV?

[crgildart]

What pressure do you run EV tires at? Aren't EVs significantly heavier than same size/category ICEVs?

Makes me wonder about braking too. Acceleration seems to be peppier with an EV even though they're heavier. Is braking also better?

 

[James]

Big wheels are mostly fashion. It's hard to find good reasons for them other than they look cool. Which sells cars soo...

It’s a freakin disease. 45 profile tires just suck driving across NH and Maine on crappy roads. Can’t imagine 35.
Let’s not forget Formula 1 had 13 inch rims till last year!

 

[cantunamunch]

Let’s not forget Formula 1 had 13 inch rims till last year!

When are you putting a vortex-sealed floor on your DD?

Seriously, all these issues derive from spending too much time at one technology level. If we design electromag suspensions with significantly lower stiction, suspension tire flex will become much less relevant.

Steering tire flex, of course, we will still need.

 

[scott43]

What pressure do you run EV tires at? Aren't EVs significantly heavier than same size/category ICEVs?

Makes me wonder about braking too. Acceleration seems to be peppier with an EV even though they're heavier. Is braking also better?

They're heavier but not crazy heavier. Probably an extra 300-500lbs on a 3000lb vehicle. But a full tank of gas changes a gas engine car's weight by typically 100lbs or so. Braking is a blend of regen and normal brakes. They do have plenty of brake. Tires are a funny thing..their behaviour at the traction limit is only partially understood. EV tires do have different compounds and construction to compensate for their characteristics. High-torque starts, heavier curb weights, more loading in cornering from that weight. Plus they want mileage. Hence the skinny tires... Theoretically traction is defined by f=mu*N, where f=friction force, mu is coeff of friction and N is the normal force. So really the tire size shouldn't matter..however..that mu value is fluid, literally and figuratively, depending on what's happening at the rubber/road interface..which itself is not really well understood. Typically, more contact patch means less weirdness so bigger typically helps in terms of overheating. it's a trade-off..

 

[anders_nor]

How was the Bmw i3 in dry and snow with those bizarre tires, 155/70/R19 !

very very good! lots of ground clearance, and the battery weights the rear so you get traction

 

[cantunamunch]

They do have plenty of brake. Tires are a funny thing..their behaviour at the traction limit is only partially understood. EV tires do have different compounds and construction to compensate for their characteristics. High-torque starts, heavier curb weights, more loading in cornering from that weight. Plus they want mileage. Hence the skinny tires... Theoretically traction is defined by f=mu*N, where f=friction force, mu is coeff of friction and N is the normal force. So really the tire size shouldn't matter..however..that mu value is fluid, literally and figuratively, depending on what's happening at the rubber/road interface..which itself is not really well understood. Typically, more contact patch means less weirdness so bigger typically helps in terms of overheating. it's a trade-off..

^It should be noted that EVs are a lot better than ICE about semi-continuously modeling available friction coefficient. For braking/regen split reasons, for torque control reasons, for vehicle stability reasons, for steer-by-wire reasons.

So, yes. Old software for doing all that could very much become a liability - one that is reflected in real-time insurance rates.

"Oh hey, you haven't downloaded an update since '21 - here's a nice monthly insurance surcharge for ya"

 

[afadeev]

Germany is going crazy for hydrogen. Bmw is coming out with the hydrogen ix5 in 2025, a fuel cell car with battery. Despite bev’s selling 1000 times more than fuel celland growing.

BMW and Toyota had bet on hydrogen decades ago, and are finding very hard to let go of a bad idea.
At least you can't fault them for not being stubborn.

Here is one explanation on why hydrogen is a BAD and DIRTY idea:

How was the Bmw i3 in dry and snow with those bizarre tires, 155/70/R19 !

For winter driving, you want narrower tires that will push through the snow down to firm ground for traction. i3 tires were perfect in that sense: car was relatively heavy, and tires were stupid narrow (I leased i3 5-6 years ago).

The downsides were also significant.
Narrow tires produce a long and narrow tire patch, so the wear rate on the tires was stupid high. Especially the rears.
Longer tire patch also increased the probability of flipping nails and bolts up and into your tire as you drove over them. I had more punctures during my 3-year i3 stint than I had with all my other cars combined, over decades. It was comically frequent (4 or 5 times?).
Lastly, those were non-standard tires developed just for the i3, so they were way more expensive than expected ($250 for fronts, $350 for rears).
Also, being narrow and tall and riding on narrow tires, the car was a handful at highway speeds. It required constant steering wheel corrections with each road crack, blast of wind, or air turbulence from nearby trucks. Driving it on a highway sucked.

It was a fun 3rd/4th car, but I would not buy it again (new), and definitely would not touch a used one with a 10-foot pole.

 

[scott43]

^It should be noted that EVs are a lot better than ICE about semi-continuously modeling available friction coefficient. For braking/regen split reasons, for torque control reasons, for vehicle stability reasons, for steer-by-wire reasons.

So, yes. Old software for doing all that could very much become a liability - one that is reflected in real-time insurance rates.

"Oh hey, you haven't downloaded an update since '21 - here's a nice monthly insurance surcharge for ya"

Being able to predict with any precision the mu value is pretty handy overall. I continue to be interested in how the "instrusion" of all these things ends up in terms of driver experience at the limit in a race track situation. I need to find someone willing to lend me their Very Expensive EV so I can beat it around the track...

 

[scott43]

Narrow tires produce a long and narrow tire patch, so the wear rate on the tires was stupid high. Especially the rears.

I suspect that was also precipitated by the fact a somewhat heavy car was riding on a 155 tire..nevermind the configuration of the tire patch. As you say, downside and a trade-off really.

 

[scott43]

This guy does ok.. Notice
not one bit of oversteer..constant plowing..

 

[cantunamunch]

This guy does ok.. Notice
not one bit of oversteer..constant plowing..

Yeh, I figure they just pick a regime and force you to stick to it... at least they can model rubber wear and weight transfer splits...

Is there an EV category in drifting champs?

 

[James]

This guy does ok.. Notice
not one bit of oversteer..constant plowing..

And then an allegedly stock Tesla Plaid S with the track package, carbon ceramic brakes- +$15k to20k if you need the bigger rear wheels, beat that by 8 seconds with a 7:25:23 lap time. Porsche Taycan had the performance package, +$14k.

The ev accelerations are just crazy. I would imagine getting used to the silence takes some time.

 

[tball]

A $70K MSRP supercharged V8 with a manual transmission sounds a lot better to me, and it's nine seconds faster:



Edit: and it won't be a brick in 20 years.

 

[Dave Marshak]

A $70K MSRP supercharged V8 with a manual transmission ...

... and it won't be a brick in 20 years.

Don't be so sure. It's just as much a brickworthy Linux machine as a Tesla, it's just attached to a big honking V8, which has it's own ways to self destruct.

dm

 

[James]

A $70K MSRP supercharged V8 with a manual transmission sounds a lot better to me, and it's nine seconds faster:

Can’t argue with that except the brick part. Though in 20yrs both things will have aftermarket hacks.

 

[crgildart]

For winter driving, you want narrower tires that will push through the snow down to firm ground for traction. i3 tires were perfect in that sense: car was relatively heavy, and tires were stupid narrow (I leased i3 5-6 years ago).

When the snow starts falling here the surface temps are often in the 40s and only cool down after a few inches have hit... making the surface SOLID ICE. You're better off with the dust on top for traction than ice on the bottom. P.S. since it's only once or twice a year tops there's not any sand or salt on the road from the previous storms..

 

[pete]

Don’t think low power ac charging at home is very detrimental.
Just because they’re done in cars doesn’t mean they’re completely done.
Repurposing ev batteries as grid storage-

B2U Storage Solutions

www.b2uco.com

quite a popular use demand on the aging EV batteries. 80% is quite happy for the home and other infrastructures. Helps solve the lack of recycling infrastructure and given there's still useful life in em

 

[pete]

there was note prior on why EVs are good and comment on Toyota being behind the curve but there does seem to be justifications on benefit of Hybrids over full EVs.

Materials, charging infrastructure, and then benefit of impact having up to 37x near term impact on emissions:

https://www.kbb.com/car-news/report-toyota-can-build-90-hybrids-or-1-ev/

or

Opinion | Targeting Toyota for Its Electric-Vehicle Heresy

Public pensions and proxy advisers try to punish the company using corporate governance as a pretext.

www.wsj.com

some of course is positioning by Toyota but still valid considerations.

 

[pete]

Neighbour has a Tesla P100D, gotta say wow is that thing insane to drive (this is get a ticket car). That said.

Motor(s) issue (apparently common) insane cost to replace, he was happy it was still under warranty.

Had and accident, still waiting for final programming to get car running (must be done at Tesla), still waiting after 3 months.

Running joke now when we see each other is "in a week...be done in a week".

Range well, for me it would be an issue, time is money, sitting somewhere to charge even on a super charger (and paying for it) doesn't make economic sense.

EV as a round town vehicle yes hands down, second vehicle gas/diesel or hybrid for the range. Longevity gas or diesel.

This an older story but seen some updates of late.

long waits can be issue for many cars with constraint parts .. know someone who waited months for their new Silverado to get a new controller for the lights. Total cost of repair another complexity

Tesla EVs, Even Mildly Damaged, Are Being Written Off by Insurance Companies

Insurers are increasingly concluding that a broken Tesla is too expensive to fix.

www.caranddriver.com

 

[anders_nor]

EV's are mostly dull for track driving vs fossil options.

i3, e-up etc, super SUPER fun for the driving around. I commute 2km to work, now.. 3 due to road closings and such. and somehow managed to drive it 20.000 km since august