RE: Detroit show: the NSX is back
Discussion
kambites said:
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As I said before though, I do think they've got the whole thing the wrong way around. The engine shouldn't be directly connected to the wheels at all - the final drive should be purely electric, IMO. Having the engine directly driving the wheels offends my sense engineering neatness.
SecondedAs I said before though, I do think they've got the whole thing the wrong way around. The engine shouldn't be directly connected to the wheels at all - the final drive should be purely electric, IMO. Having the engine directly driving the wheels offends my sense engineering neatness.
Edited by kambites on Friday 13th January 09:16
kambites said:
Hydrogen is not a valid form of energy storage until we can generate vast quantities of electricity cheaply or come up with a fundamentally more efficient way of generating hydrogen. Realistically that probably means it's no use until we get financially viable nuclear fusion generators.
Ultimately all technology is dead-end. It's just a question of when. I think ICE/electric hybrids have got a good thirty years if not substantially longer before anything comes along which can better them. I doubt hydrogen will be viable as a primary energy storage medium for automotive transport in my life-time.
ETA: Having said that, I think mild hybrids of this type are going to hit their dead-end much sooner than that. As soon as someone introduces a really viable range extender type hybrid drive-train, I think it will be the beginning of the end for both mild hybrids and simple ICE powered cars.
I would hope that battery technology moves on enough and/or service stations enable batteries to be swapped in seconds that most people won't need range extendersUltimately all technology is dead-end. It's just a question of when. I think ICE/electric hybrids have got a good thirty years if not substantially longer before anything comes along which can better them. I doubt hydrogen will be viable as a primary energy storage medium for automotive transport in my life-time.
ETA: Having said that, I think mild hybrids of this type are going to hit their dead-end much sooner than that. As soon as someone introduces a really viable range extender type hybrid drive-train, I think it will be the beginning of the end for both mild hybrids and simple ICE powered cars.
Edited by kambites on Friday 13th January 08:58
kambites said:
I don't understand that comment. This thread is full of reasons to have a hybrid even if you run the ICE constantly. That's the primary purpose of a hybrid drive system.
As I said before though, I do think they've got the whole thing the wrong way around. The engine shouldn't be directly connected to the wheels at all - the final drive should be purely electric, IMO. Having the engine directly driving the wheels offends my sense engineering neatness.
Energy is a bar of soap though, everytime you handle it you lose some. And imagine the power electronics to deal with that aswell as the cable diameter, all tractive effort delivered through cables with losses rather than a proper engine link to get more power to the wheels and need less heat management and allow..... plus in a sports car... no thanksAs I said before though, I do think they've got the whole thing the wrong way around. The engine shouldn't be directly connected to the wheels at all - the final drive should be purely electric, IMO. Having the engine directly driving the wheels offends my sense engineering neatness.
Edited by kambites on Friday 13th January 09:16
GM had that concept with the volt, until they realised direct coupling to the crank for charge sustained cruise gives +15% MPG. Although that is a 1.4 Corsa engine rather than a proper REEV engine where you would atleast jump from Otto to Atkinson cycle like the Prius... hence the engine is not great for throttle response and should not form part of any conversation with the NSX. The NSX will have to be a cheaper, slower Jaguar CX75, which is exactly what it will be.
Thing is, a range-extender supercar loses one, rather key, feature - SOUND! Why would you want a supercar that doesn't sound of much?
For a mainstream car, no problem - most of them don't sound of much anymore already, so I'm quite happy to go the whole hog, as long as the rest of the package works (throttle-response is guaranteed, after all!).
But for a sports car / supercar / hell, almost any 'fun' car, it's missing the point somewhat. May as well ask if you'd buy a diesel Lambo, FFS...
For a mainstream car, no problem - most of them don't sound of much anymore already, so I'm quite happy to go the whole hog, as long as the rest of the package works (throttle-response is guaranteed, after all!).
But for a sports car / supercar / hell, almost any 'fun' car, it's missing the point somewhat. May as well ask if you'd buy a diesel Lambo, FFS...
JonnyVTEC said:
Energy is a bar of soap though, everytime you handle it you lose some. And imagine the power electronics to deal with that aswell as the cable diameter, all tractive effort delivered through cables with losses rather than a proper engine link to get more power to the wheels and need less heat management and allow..... plus in a sports car... no thanks
Going through an electrical phase is more efficient than going through a gearbox. havoc said:
Thing is, a range-extender supercar loses one, rather key, feature - SOUND! Why would you want a supercar that doesn't sound of much?
For a mainstream car, no problem - most of them don't sound of much anymore already, so I'm quite happy to go the whole hog, as long as the rest of the package works (throttle-response is guaranteed, after all!).
But for a sports car / supercar / hell, almost any 'fun' car, it's missing the point somewhat. May as well ask if you'd buy a diesel Lambo, FFS...
I think I'll wait to see(hear) what it sounds like before judging that aspect.For a mainstream car, no problem - most of them don't sound of much anymore already, so I'm quite happy to go the whole hog, as long as the rest of the package works (throttle-response is guaranteed, after all!).
But for a sports car / supercar / hell, almost any 'fun' car, it's missing the point somewhat. May as well ask if you'd buy a diesel Lambo, FFS...
Didn't realise until I saw a Hi-Res photo of it at a particular angle - that there's a nifty bit of wrapped around rear window/roof line gap going on at the back end 
kambites said:
I suspect still lighter than a gearbox and differential.
Shame youd need a massive battery to start with to even think about sustained 300kW then? Even a small peak is would be a challenge whilst engine sped up to speed. 'Suspect' is just you guessing? Its a Honda NSX rather than a drag car so performance needs to be available for more than 10 seconds bursts. A decent REEV will need a gearbox anyway, albeit a light 3 speeder.
Edited by JonnyVTEC on Monday 16th January 09:41
JonnyVTEC said:
kambites said:
I suspect still lighter than a gearbox and differential.
Shame youd need a massive battery to start with to even think about sustained 300kW then? 'Suspect' is just you guessing?
In your haste to ridicule hybrids you didn't actually bother read what I'm talking about did you? The discussion that you're commenting on was about continuously variable transmissions - nothing to do with batteries, simply a way to get motive force from an internal combustion engine to the wheels without the need for a link between engine speed and wheel speed. It was refering to a set engine speed. The typical comment that usually pulls in the comparison to diesel electric locomotives? Nothing to do with CVT, CVT would still be a direct link......without oversizing the power electronics.
Im not dismissing hybrids. Just taking a stance that a performance hybrid should have a direct link to the engine for the bulk of the power transmission to the wheels.
Im not dismissing hybrids. Just taking a stance that a performance hybrid should have a direct link to the engine for the bulk of the power transmission to the wheels.
JonnyVTEC said:
It was refering to a set engine speed. The typical comment that usually pulls in the comparison to diesel electric locomotives? Nothing to do with CVT, CVT would still be a direct link......without oversizing the power electronics.
Of course it's a CVT. No-one said a transmission has to be mechanical. A transmission is just a means of getting power from the the engine to the wheels. Anyway, so why were you talking about batteries?
kambites said:
Of course it's a CVT. No-one said a transmission has to be mechanical. A transmission is just a means of getting power from the the engine to the wheels.
Anyway, so why were you talking about batteries?
Huh?Anyway, so why were you talking about batteries?
The NSX is going to be equipped with a 7 speed DSG Gearbox.
A CVT engine powers the wheels through the belts and driveshafts.
The Honda Insight 2 is an example Ill pull on. Its CVT. 88bhp or so with CVT, the IMA system adds 10kW of power. If the vehicle was a series hybrid not parallel the Inverter and cables would be rated to 120kW and not 10kW..... ie bigger and heavier.
Batteries.... stamp on the power and you want it straight away but the engine isnt up to speed? You want 300kW, even with an optimistic 10C discharge battery pack you would need a pack bigger than the Nissan Leafs. And you want that in a Super Car along with 3 electric motors and a 3.5L V6?
kambites said:
As I said before though, I do think they've got the whole thing the wrong way around. The engine shouldn't be directly connected to the wheels at all - the final drive should be purely electric, IMO. Having the engine directly driving the wheels offends my sense engineering neatness.
I disagreed with this point for the reason stated above, its also a vehicle packaging and mass nightmare. Edited by JonnyVTEC on Monday 16th January 09:57
JonnyVTEC said:
Huh?
The NSX is going to be equipped with a 7 speed DSG Gearbox.
A CVT engine powers the wheels through the belts and driveshafts.
Ah yes sorry, we'd drifted off topic rather during all the general talk about hybrids. We were talking about CVTs, nothing to do with batteries at all. The NSX is going to be equipped with a 7 speed DSG Gearbox.
A CVT engine powers the wheels through the belts and driveshafts.
In the case of range-extender hybrids, surely you use bloody great capacitors to smooth out the load on the batteries? I just really dislike the idea of having an engine that should be capable of 40%ish efficiency, and fundamentally limiting it to about 20% by connecting it to the wheels.
We'll know in the next year or so, I think there are several range extender systems coming onto the market. Personally I suspect the direct drive ICE will die shortly after they do.
Edited by kambites on Monday 16th January 09:58
SWoll said:
Mr Gear said:
Bladedancer said:
Though it is a bit sad people choose to promote this hybrid thing over proper alternative fuel cars like Honda Clarity.
You're joking, right?People who extol the virtues of hydrogen cars without understanding their limitations are in no position to knock what you can achieve with a hybrid.
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