Could it be the end of the spark plug?

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Wed 18 Jan 2017 21:25
Could it be the end of the spark plug? - Fishermans Bend

www.wheelsmag.com.au/news/1701/mazda-ditches-spark...s

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Wed 18 Jan 2017 23:18
Could it be the end of the spark plug? - bathtub tom

I'd like to know what compression ratio they're running for that, the engine's expectant life and what happens in cold weather?

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Thu 19 Jan 2017 08:08
Could it be the end of the spark plug? - gordonbennet

Me too BT.

Seeing the problems so many modern Diesels have (Mazda Diesels of recent years a shining example) are we sure this is necessarily a winner?

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Thu 19 Jan 2017 08:44
Could it be the end of the spark plug? - elekie&a/c doctor

Looks like a few makers are trialing this system.www.caranddriver.com/features/hyundais-experimenta...e

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Thu 19 Jan 2017 09:01
Could it be the end of the spark plug? - FP

"I'd like to know what compression ratio they're running for that.."

Mazda 2-litre Skyactiv-G petrol engines are already running at 14:1, which is near diesel territory. Knocking is prevented by the shape of the piston head and design of the exhaust manifold. I assume Mazda have simply pursued this design philosophy further.

"...and what happens in cold weather?"

No idea. Glow plugs?

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Thu 19 Jan 2017 09:20
Could it be the end of the spark plug? - RT

The Mazda Skyactiv-D diesel compression ratio is 14:1, low by diesel standards, but the same 14:1 used in the Skyactiv-G petrol engines.

Skyactiv-G 2nd generation will use 18:1 compression ratio

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Thu 19 Jan 2017 09:41
Could it be the end of the spark plug? - thirts

I thought petrol engines advanced the ignition timing as the revs increase, how will this do that?

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Thu 19 Jan 2017 11:36
Could it be the end of the spark plug? - brum

IIRC when I read about HCCI a few years ago, when it was more a novelty lab thing with manufacturers (GM I think), the problem with HCCI was it was very difficult to control, only working in a narrow range of conditions, with a tendency for it to stop working sporadically. Then, I think they had spark plugs, to start the engine conventionally, and it would go into HCCI mode when cruising on light thottle, falling back to conventional when under load.

I might be wrong, but I doubt theyve ditched the spark plugs.

Edited by brum on 19/01/2017 at 11:39

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Thu 19 Jan 2017 12:29
Could it be the end of the spark plug? - gordonbennet

It used to be the opposite problem of stopping the engine running at one time, when carbon build up would glow red and ignite the fuel mixture, which being via carb fed would keep it going for some time.

Next they'll be telling us that carbon build up in an engine is a thing of the past, but if these designs go ahead could cause problems as mileage rises.

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Thu 19 Jan 2017 13:33
Could it be the end of the spark plug? - FP

"Next they'll be telling us that carbon build up in an engine is a thing of the past..."

Thanks to modern petrol additives, I thought it already was. When did I last hear of an engine going in for a de-coke?

Or have I got this wrong?

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Thu 19 Jan 2017 13:46
Could it be the end of the spark plug? - RT

"Next they'll be telling us that carbon build up in an engine is a thing of the past..."

Thanks to modern petrol additives, I thought it already was. When did I last hear of an engine going in for a de-coke?

Or have I got this wrong?

You've not heard of all the issues with GDi engines then ?

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Thu 19 Jan 2017 19:26
Could it be the end of the spark plug? - Engineer Andy

I'll reserve judgement until the new tech has been in their cars (or others doing the same) for a good 3-5 years at least - my conservatism on buying cars with new tech, such as start-stop, small-engined petrol turbo cars, dual clutch gearboxes and those with an arrany of three-lettered acronymn features has served me well in terms of reliability over the years.

Don't see any reason (even if I am a very satisfied Mazda customer) to stop this approach any time soon...though I may have to relent a bit if I do go for a new Mazda (currently looking for a new car) as all their 3s come with electronic handbrakes...

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Thu 19 Jan 2017 19:35
Could it be the end of the spark plug? - brum

By 2018 we'll all be driven around by autonomous tesla 3's, provided you have the app of course....probably desperately trying to find an unoccupied charging point!

:)

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Thu 19 Jan 2017 20:24
Could it be the end of the spark plug? - Bolt

By 2018 we'll all be driven around by autonomous tesla 3's, provided you have the app of course....probably desperately trying to find an unoccupied charging point!

:)

I wont,I dont trust em and have no intensions of using or buying one,I will stick to diesel as long as I can, and personally think they will, along with petrol become more efficient.

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Thu 19 Jan 2017 21:02
Could it be the end of the spark plug? - RT

By 2018 we'll all be driven around by autonomous tesla 3's, provided you have the app of course....probably desperately trying to find an unoccupied charging point!

:)

Don't worry - only the wealthy can afford a Tesla and we're still going to be driving gas-guzzlers.

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Thu 19 Jan 2017 22:23
Could it be the end of the spark plug? - Big John

Especially as the Tesla will be hit by the new car tax regime from April 2017!

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Thu 19 Jan 2017 23:43
Could it be the end of the spark plug? - Sofa Spud

To me this is a diesel engine, albeit one that runs on petrol! I imagine it would sound like a diesel too. After all, normal engines make a sort of diesel sound when they're suffering from pre-ignition, or 'pinking'. I don't see why the author of the article thinks engines with high compression ratios aren't suited to turbocharging - most diesels are turbocharged and they need high compression ratios to work at all. Maybe the compression-ignition petrol engine would need a much higher c.r. still.

Given all the development going into electric cars, and particularly batteries and fast charging, I reckon this Mazda idea will go the way of hydrogen power, rotary engines and automotive gas turbines.

As for autonomous Tesla 3's. I think electric cars will gain in popularity much more quickly that autonomous driving technology.

Edited by Sofa Spud on 19/01/2017 at 23:48

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