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Porsche's idea for a six-stroke internal combustion engine

motor1.com

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Re: Porsche's idea for a six-stroke internal combustion engine

#331

Post by AtlasBarfed »

xxs wrote: post #39
AtlasBarfed wrote: post #20

Earlier quoted context omitted.

On top of that, the commenter is completely ignorant of the rise of saltwater batteries which don't even use lithium. Also probably unaware that with the rise of extremely low cost, solar and wind, Fossil fuel use on the grid is economically nonviable long term. Even so, the fossil fuels consumed on the grid are very likely to be combined cycle natural gas, which has less carbon emissions than have equivalent. Amount…

>On top of that, the commenter is completely ignorant of the rise of saltwater batteries which don't even use lithium. I'd not call the rise, yet. The Na ones' energy density (and specific energy) is even lower than Li based (LiFePO4 is lower than cobalt ones). They might be okay for grid storage, of course.

Saltwater batteries and lfp batteries don't require nearly as much active heating and safety measures as nmc chemistries.

So the pack level they become a lot more competitive. Rise of high density, salt, water and lfp. We should be able to produce 300 and 400 mile range sedans with sodium ion and LFP chemistries.

Just go look at the catl density numbers all the stuff they have going into production. Obviously has not scaled to the level it needs to. That's a big ramp up.

I believe the current numbers are 160 Watt hours per kilogram for sodium ion and a little over 200 for lfp. With cell to pack projections of 90%, while pack density of nmc is like 60-70% to the cooling and safety system requirements, sodium ion is a revolutionary development for the cheap EV.

The five year road maps for sodium ion gets it close to 200 watt hours per kilogram. Lfp should be reaching 250 Watt hours per kilogram in the next five years.

Re: Porsche's idea for a six-stroke internal combustion engine

#332

Post by jamescmartinez »

digga3000 wrote: post #330

This article has brought out a lot people to comment who don't know anything about sports cars, but feel necessary to insist they do. It's bad enough that I had to login in to dispell this reoccurring canard: "EVs are faster in a straight line! EVs have a flat/high torque curve!" -- big whoop. 1) 0-60 times are biased against ICEs as their torque curves _aren't_ flat and so the start of range is mostly when the engin…

Your second point misses an important fact: the Tesla Model S Plaid set a 7:25 Nurburgring lap time, and the Porsche Taycan did it in 7:07. Both of these lap times are faster than many high-performance ICE cars, and close to GT2/3 times which are just below 7:00.

As you might expect, the technology will continue to evolve, too.

Re: Porsche's idea for a six-stroke internal combustion engine

#333

Post by DiggyJohnson »

philistine wrote: post #326
kevin_thibedeau wrote: post #310

Earlier quoted context omitted.

New York is mostly a semi-rural state where long distance travel in a BEV is a problem. One city where most residents don't drive doesn't mean anything.

One city ? One city !? Electrification will happen for the vast majority of people. Of course, a small minority won’t be able to make the switch right away and will have to hang on to gas. That’s fine! Even to this day, 98% of houses have refrigerators. According to your logic, we shouldn’t allow businesses to sell refrigerated milk because of this 2%.

They never said it shouldn’t be allowed.

Re: Porsche's idea for a six-stroke internal combustion engine

#334

Post by 6SixTy »

randerson wrote: post #221
kopirgan wrote: post #212

Know nothing about automobile engineering but somehow this feels like WordPerfect releasing a fantastic version for DOS when Windows was already capturing all the market. Btw they did that. Rest is history.

I actually miss DOS. I could focus on one task for hours without being distracted by other apps trying to get my attention. There was something raw and engaging about being a few layers closer to the hardware without all the bloat. And, while I'd never go back to mechanical hard drives, you could hear the computer 'thinking'. It was more visceral. I think it's a great analogy. It's all the little quirks and flaws tha…

Do you actually miss DOS or just long for the CLI? Due to the culture of the x86 ecosystem, DOS hasn't gone anywhere; and the CLI is pretty much the default UI for most UNIX like operating systems out there.

Re: Porsche's idea for a six-stroke internal combustion engine

#335

Post by _yb2s »

dahart wrote: post #328
_yb2s wrote: post #319

Earlier quoted context omitted.

Porsche cares a lot about efficiency, and their cars are generally designed to be very efficient- but they use the extra efficiency to sell a more powerful car, not a more fuel efficient car. Beyond some historical agricultural tractors, Porsche has only ever made high performance cars, they don't make general purpose "commuter" or "family" cars. Even their large SUVs like the Cayenne are very high performance vehicl…

The base model Cayenne takes almost 6 seconds to get to 60mph when floored. That’s not particularly fast, even by family SUV standards, it’s comparable to a Honda Passport, and slower than SUVs from Audi, BMW, and Ford, and quite a few others. The Cayenne is an SUV in the first place. What exactly is a publicly available SUV if not a general purpose family commuter car? One of my friends bought a Cayenne to shuttle h…

The Cayenne (and also the VW Touareg which is it based on) is an offroad exotic supercar platform from the bottom up- the handling, engineering, etc. is really unique. It is also, by now, and outdated design that is over 20 years old and not changed very much. It is also a very heavy vehicle with a suspension and chassis that can survive hard offroad racing- jumping it large distances, and landing it hard, etc. The frame, suspension, etc. - it can also tow as much as a full sized pickup truck.

You can get a base model with a smaller engine, but it is still a high performance car design from the ground up. They are also pretty small inside- not much more room than a VW Golf. Yes, (wealthy) people take their kids to school and soccer practice in them. I also take my kid to school in my Boxster... which also on paper is slower than a lot of regular Japanese passenger cars, which in practice it could easily lap on a track because it handles so much better.

To really understand the Cayenne, look at a fully equipped model with air suspension, multiple differential locks, skid plates, sway bar disconnects, and a twin turbo V8 - and look at what people on YouTube do with them. Also look at the V10 and V12 Touareg models.

If you're into performance car driving, you will notice that a Cayenne drives nothing like those other SUVs even if the specs on paper are the same. On a track (off road or paved) with a skilled driver it will easily lap those other vehicles. Specs don't account for finely tuned weight distribution, handling, braking, steering etc. that make a Porsche a Porsche, or the fact that all of the systems (oil supply, etc.) can survive sustained high rpm high g-force track use which would destroy other cars quickly.

You are also misunderstanding my point about efficiency- obviously Porsche cares about efficiency, but they don't design or advertise their vehicles to get low fuel consumption. Efficiency factors into the overall vehicle- more powerful, more range, etc. Improved fuel efficiency is also a selling point, but not the main one.

Re: Porsche's idea for a six-stroke internal combustion engine

#336

Post by erik_seaberg »

philistine wrote: post #326
kevin_thibedeau wrote: post #310

Earlier quoted context omitted.

New York is mostly a semi-rural state where long distance travel in a BEV is a problem. One city where most residents don't drive doesn't mean anything.

One city ? One city !? Electrification will happen for the vast majority of people. Of course, a small minority won’t be able to make the switch right away and will have to hang on to gas. That’s fine! Even to this day, 98% of houses have refrigerators. According to your logic, we shouldn’t allow businesses to sell refrigerated milk because of this 2%.

That's because apartments and houses have indoor power, which took a while. Neighborhood streets still don't have outdoor power at every curb.

Re: Porsche's idea for a six-stroke internal combustion engine

#337

Post by flir »

citrin_ru wrote: post #58
thebruce87m wrote: post #28

Earlier quoted context omitted.

Many of the myths you are posting are busted here: https://www.carbonbrief.org/factcheck-21-misleading-myths-ab... The national grid in the UK was so fed up with people making claims about the grid capacity it also busted some too: https://www.nationalgrid.com/stories/journey-to-net-zero/ele... > The highest peak electricity demand in the UK in recent years was 62GW in 2002. Since then, the nation’s peak demand has f…

> Since then, the nation’s peak demand has fallen by roughly 16% due to improvements in energy efficiency. Energy demand in UK declining because prices went up which accelerated deindustrialisation and forced people's to use less energy e. g. heat homes less .

LED bulbs (90% less energy), LCD TVs (75% less energy). It adds up.

Re: Porsche's idea for a six-stroke internal combustion engine

#338

Post by flir »

Symbiote wrote: post #99
azherebtsov wrote: post #34

Earlier quoted context omitted.

I’m particularly interested in last three points. Do you mind to share some data? For instance, where one recycle a Tesla battery, say in Poland? I do not see to many chargers around and I believe the grid is not very modern here. Why do you think it can easily handle millions EVs? What about peak hours like nights? Do you think it will be env friendly, provided that majority of electricity in Poland is produced on c…

The battery can be recycled in Germany if Poland doesn't have the facility.

I think shifting them to static applications when they hit 70% capacity makes more sense, personally. For now, just recycle the ones that have actually failed. Or even just warehouse them until they can be recycled.

(Whether we actually do that or not, capitalism being what it is....)

Re: Porsche's idea for a six-stroke internal combustion engine

#339

Post by _DeadFred_ »

jamescmartinez wrote: post #332
digga3000 wrote: post #330

This article has brought out a lot people to comment who don't know anything about sports cars, but feel necessary to insist they do. It's bad enough that I had to login in to dispell this reoccurring canard: "EVs are faster in a straight line! EVs have a flat/high torque curve!" -- big whoop. 1) 0-60 times are biased against ICEs as their torque curves _aren't_ flat and so the start of range is mostly when the engin…

Your second point misses an important fact: the Tesla Model S Plaid set a 7:25 Nurburgring lap time, and the Porsche Taycan did it in 7:07. Both of these lap times are faster than many high-performance ICE cars, and close to GT2/3 times which are just below 7:00. As you might expect, the technology will continue to evolve, too.

This person is explicitly ignoring that EVs use tire and braking configurations that maximize efficiency over performance in order to make their point. It's like saying ICE cars are inherently bad at performance because of Ferdinand Porsche's VW Beetle design choices or because my 3000lb vehicle (lighter than a modern Porsche) Jeep XJ isn't a sports car ICE vehicles can't be performance vehicles.

Re: Porsche's idea for a six-stroke internal combustion engine

#340

Post by flir »

hnlmorg wrote: post #186
quintushoratius wrote: post #176

Earlier quoted context omitted.

>> Automotive batteries have been demonstrated as >90% recyclable, far better than most materials we consider "recyclable" today such as plastic > Citation needed It shouldn't be hard to believe. The components of a battery aren't consumed during operation. An old battery weighs the same as a new battery, and the chemical reactions taking place inside are reversible (because that's how a chemical battery works). I be…

> in my experience in the US, charging away from home is far more expensive We have lots of free charging points in the UK. Or at least they do around me. > Your statement about your cost comparison doesn't mention maintenance, which is a significant savings. No oil changes, no rusted exhaust pipes, no spark plugs, etc. Over the life of the car, that's tens of thousands of dollars unspent. In my experience the mainte…

> We have lots of free charging points in the UK

Wait, we do? There are people out there just giving away energy?

(I think I must have misunderstood you here).

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