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Auto Talk => General Automotive => Topic started by: Laconian on August 08, 2017, 03:30:27 PM

Title: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Laconian on August 08, 2017, 03:30:27 PM
http://www2.mazda.com/en/publicity/release/2017/201708/170808a.html
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: shp4man on August 08, 2017, 03:48:37 PM
Quote from: Laconian on August 08, 2017, 03:30:27 PM
http://www2.mazda.com/en/publicity/release/2017/201708/170808a.html

Nice. Hope they're successful.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: 12,000 RPM on August 08, 2017, 04:08:39 PM
Big stuff. I hear the supercharger will be powered electrically too. Just in time too, because Skyactiv-G engines are no good in their mainstreamers. Too effing slow, same gas mileage as VW's punchier TSI lumps.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: RomanChariot on August 08, 2017, 04:09:54 PM
Quote
Spark Controlled Compression Ignition overcomes two issues that had impeded commercialization of compression ignition gasoline engines: maximizing the zone in which compression ignition is possible and achieving a seamless transition between compression ignition and spark ignition.

So a compression ignition engine with a spark plug? I don't really care if it gives the gains they are claiming.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Laconian on August 08, 2017, 04:32:58 PM
Quote from: 12,000 RPM on August 08, 2017, 04:08:39 PM
Big stuff. I hear the supercharger will be powered electrically too. Just in time too, because Skyactiv-G engines are no good in their mainstreamers. Too effing slow, same gas mileage as VW's punchier TSI lumps.

That's kind of surprising. IIRC supercharging has pretty high parasitic losses (on the order of tens of HPs?). An electric supercharger would presumably necessitate a beefier/higher voltage electrical system to handle the beefier charging, storage, and output loads.

I'm betting they use a regular supercharger, with automatic clutches for disengaging the unit when not desired.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: MrH on August 08, 2017, 04:41:33 PM
Yesssss. I've been crossing my fingers for this for ages.

If this is dropping into the current mazda3, I hope it comes to a face lifted Miata.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: 93JC on August 08, 2017, 04:52:49 PM
Quote from: 12,000 RPM on August 08, 2017, 04:08:39 PM
Just in time too, because Skyactiv-G engines are no good in their mainstreamers. Too effing slow, same gas mileage as VW's punchier TSI lumps.

wat

Mazda 3 2.0 L = 155 hp, 7.9 s 0-60, 28/37 city/hwy
VW Golf TSI = 170 hp, 7.3 s, 25/35
Mazda 3 2.5 L = 185 hp, 6.8 s, 27/36

(0-60 times from C&D, EPA mileage ratings)
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Laconian on August 08, 2017, 04:54:46 PM
:hesaid:

I don't know where you get some of this shit from, Sporty. The current SkyActiv engines are very nice. Just not as nice as the Honda turbo 4s.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Soup DeVille on August 08, 2017, 05:12:01 PM
Quote from: Laconian on August 08, 2017, 04:32:58 PM
That's kind of surprising. IIRC supercharging has pretty high parasitic losses (on the order of tens of HPs?). An electric supercharger would presumably necessitate a beefier/higher voltage electrical system to handle the beefier charging, storage, and output loads.

I'm betting they use a regular supercharger, with automatic clutches for disengaging the unit when not desired.

An electric supercharger could also be nearly infinitely variable. It would however, unless there was a relatively large bypass plenum, need to be moving at all speeds and could never actually shut off, otherwise it would starve the engine.

Electric super chargers have been used before, but usually as short term power boosters.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: cawimmer430 on August 08, 2017, 05:20:22 PM
Isn't it also the characteristics of the fuel that play an important role in how and when it combusts?

Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: r0tor on August 08, 2017, 07:21:21 PM
Quote from: Soup DeVille on August 08, 2017, 05:12:01 PM
An electric supercharger could also be nearly infinitely variable. It would however, unless there was a relatively large bypass plenum, need to be moving at all speeds and could never actually shut off, otherwise it would starve the engine.

Electric super chargers have been used before, but usually as short term power boosters.

Unless it's an electric centrifugal supercharger


Anyways, mazda is dead to me until they can manage to build something with a 0-60 time at least in the low 5 sec range
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Soup DeVille on August 08, 2017, 07:22:08 PM
Quote from: r0tor on August 08, 2017, 07:21:21 PM
Unless it's an electric centrifugal supercharger


Anyways, mazda is dead to me until they can manage to build something with a 0-60 time at least in the low 5 sec range

It would still have to rotate, wouldn't it?
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: giant_mtb on August 08, 2017, 07:26:34 PM
Quote from: cawimmer430 on August 08, 2017, 05:20:22 PM
Isn't it also the characteristics of the fuel that play an important role in how and when it combusts?



Yeah, and now that gasoline and diesel are so highly standardized and widely available, they have to design the engine around the fuel instead of the other way around.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: 12,000 RPM on August 08, 2017, 08:13:10 PM
Quote from: 93JC on August 08, 2017, 04:52:49 PM
wat

Mazda 3 2.0 L = 155 hp, 7.9 s 0-60, 28/37 city/hwy
VW Golf TSI = 170 hp, 7.3 s, 25/35
Mazda 3 2.5 L = 185 hp, 6.8 s, 27/36

(0-60 times from C&D, EPA mileage ratings)

Quote from: Laconian on August 08, 2017, 04:54:46 PM
:hesaid:

I don't know where you get some of this shit from, Sporty. The current SkyActiv engines are very nice. Just not as nice as the Honda turbo 4s.
All I know is the 3 2.0L I rented felt like it was down 100HP vs the Golf TSI. I'm sure with 700lb less curb weight that 2.0L would feel great.... but in the 3 it was a dog. I'm still reeling from disappointment with how that thing drove.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: r0tor on August 08, 2017, 08:27:50 PM
Quote from: Soup DeVille on August 08, 2017, 07:22:08 PM
It would still have to rotate, wouldn't it?

Centrifugal pumps are not positive displacement... They will allow flow through the pump even if it's not moving
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: MX793 on August 08, 2017, 08:29:52 PM
Quote from: 12,000 RPM on August 08, 2017, 08:13:10 PM
All I know is the 3 2.0L I rented felt like it was down 100HP vs the Golf TSI. I'm sure with 700lb less curb weight that 2.0L would feel great.... but in the 3 it was a dog. I'm still reeling from disappointment with how that thing drove.

Different type of power delivery.  The TSI makes all of its power in the low to midrange.  At 4000 RPM, it's making 25% more power than the Mazda. 

And that's not accounting for differences in how the throttle pedals are calibrated.  It's easy to make a car "feel" quicker simply by calibrating the pedal more aggressively (e.g., open the throttle by 40 or 50% when the pedal is only depressed 1/4 of its stroke).
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: MX793 on August 08, 2017, 08:30:50 PM
Quote from: r0tor on August 08, 2017, 08:27:50 PM
Centrifugal pumps are not positive displacement... They will allow flow through the pump even if it's not moving

True, but it will still result in a restriction in the intake path.  While it won't necessarily starve the engine, it would be like running with a clogged air filter.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Soup DeVille on August 08, 2017, 09:18:34 PM
Quote from: r0tor on August 08, 2017, 08:27:50 PM
Centrifugal pumps are not positive displacement... They will allow flow through the pump even if it's not moving

I know that, but there has to be a pretty big restriction involved.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: GoCougs on August 08, 2017, 09:24:27 PM
Quote from: Laconian on August 08, 2017, 04:32:58 PM
That's kind of surprising. IIRC supercharging has pretty high parasitic losses (on the order of tens of HPs?). An electric supercharger would presumably necessitate a beefier/higher voltage electrical system to handle the beefier charging, storage, and output loads.

I'm betting they use a regular supercharger, with automatic clutches for disengaging the unit when not desired.

Well, those parasitic losses are there whether belt or electric motor driven ;). But as we're seeing in the real world, turbos have no mpg advantage over S/C (but turbos are cheaper to make).

Could be there is a hybrid system that powers the S/C drive motor for intermittent use (I mean, how often would a econobox need continuous max power?).

Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Laconian on August 08, 2017, 09:33:45 PM
Right, my point is that it will take many watts to drive an electric S/C, more than a regular 12v lead acid can provide.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: 12,000 RPM on August 09, 2017, 06:07:16 AM
Quote from: Laconian on August 08, 2017, 09:33:45 PM
Right, my point is that it will take many watts to drive an electric S/C, more than a regular 12v lead acid can provide.
I think they are jumping on the 48V mild hybrid wave.

Quote from: GoCougs on August 08, 2017, 09:24:27 PM
Well, those parasitic losses are there whether belt or electric motor driven
Are they losses if the power comes from regenerative braking?

Quote from: MX793 on August 08, 2017, 08:29:52 PM
Different type of power delivery.  The TSI makes all of its power in the low to midrange.  At 4000 RPM, it's making 25% more power than the Mazda. 
I mean, that's where you spend your time on the street. The TSI was faster short shifting at ~4K than the Mazda 2.0 was to redline... which makes sense as the TSI is rated for like 15% more power (but really makes like 30% more). But they got the same exact gas mileage over the same commutes within weeks of each other.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: MrH on August 09, 2017, 07:21:47 AM
Quote from: Laconian on August 08, 2017, 09:33:45 PM
Right, my point is that it will take many watts to drive an electric S/C, more than a regular 12v lead acid can provide.


Mazda has been using that i-Loop capacitor system to improve fuel economy for awhile....  That's what immediately comes to mind when I hear electric supercharger.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: cawimmer430 on August 09, 2017, 12:52:01 PM
Quote from: giant_mtb on August 08, 2017, 07:26:34 PM
Yeah, and now that gasoline and diesel are so highly standardized and widely available, they have to design the engine around the fuel instead of the other way around.

And this means this engine can only be sold in certain shall we say "developed" markets where the fuel quality can be guaranteed.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Laconian on August 09, 2017, 12:53:40 PM
Quote from: cawimmer430 on August 09, 2017, 12:52:01 PM
And this means this engine can only be sold in certain shall we say "developed" markets where the fuel quality can be guaranteed.

True, diesel engines are really good at burning low quality fuel oil.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: giant_mtb on August 09, 2017, 12:54:15 PM
Quote from: cawimmer430 on August 09, 2017, 12:52:01 PM
And this means this engine can only be sold in certain shall we say "developed" markets where the fuel quality can be guaranteed.

...just like every other gasoline car sold today...? :huh:
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: cawimmer430 on August 09, 2017, 12:57:17 PM
Quote from: giant_mtb on August 09, 2017, 12:54:15 PM
...just like every other gasoline car sold today...? :huh:

I believe some makes sell newer cars with older low-tech engines in some markets, like in most of Africa for example because of their poor or fluctuating fuel quality (and general lack of care about emissions).
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: giant_mtb on August 09, 2017, 01:23:07 PM
Quote from: cawimmer430 on August 09, 2017, 12:57:17 PM
I believe some makes sell newer cars with older low-tech engines in some markets, like in most of Africa for example because of their poor or fluctuating fuel quality (and general lack of care about emissions).

I doubt Mazda gives a shit about that market.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: cawimmer430 on August 09, 2017, 01:36:29 PM
Quote from: giant_mtb on August 09, 2017, 01:23:07 PM
I doubt Mazda gives a shit about that market.

They should. They can sell all the Wankel engines they want over there and nobody will piss on them about something so trivial like emissions!
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: 12,000 RPM on August 09, 2017, 05:26:40 PM
Quote from: cawimmer430 on August 09, 2017, 12:57:17 PM
I believe some makes sell newer cars with older low-tech engines in some markets, like in most of Africa for example because of their poor or fluctuating fuel quality (and general lack of care about emissions).
They sell new Benzes in Ghana

http://mercedes-benz.com.gh/

Mazda is not a huge volume player anyway and developing markets have zero profit. So even without those issues they are probably sticking to the developing world.

Plus the way this thing works should be able to run on shit gas. It's basically controlled knock
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Laconian on August 09, 2017, 05:38:18 PM
Our hypothetical implementation would definitely be much pricier than what people from developing countries can afford.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: 93JC on August 10, 2017, 11:20:21 AM
Quote from: MX793 on August 08, 2017, 08:29:52 PM
And that's not accounting for differences in how the throttle pedals are calibrated.  It's easy to make a car "feel" quicker simply by calibrating the pedal more aggressively (e.g., open the throttle by 40 or 50% when the pedal is only depressed 1/4 of its stroke).

Something I complained about in my test drive of a MkV GTI (2009)...

My buddy's Golf Wagon (2015 or '16) isn't bad for it though, but his 1.8 TSI doesn't feel any more spritely than my 2.5 L (non-SkyActiv) Mazda 3. Which makes sense, because mine's 167 hp and his has a scant 3 hp advantage over it.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: MrH on August 10, 2017, 11:47:24 AM
Just imagine a 2.0 liter, making something like 170 hp, 200 lb/ft of torque, in an ND Miata, getting 55 mpg on the highway :wub:
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Xer0 on August 10, 2017, 12:06:35 PM
That engine would rev to like 5K RPM and ruin half the fun of a Miata.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: 12,000 RPM on August 11, 2017, 06:06:58 AM
Yea it needs to zing

Mazda needs to take more advantage of that 14:1 or whatever compression ratio.... let that motherfucker wind out like a rotary.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: AutobahnSHO on August 11, 2017, 08:14:29 AM
Quote from: Xer0 on August 10, 2017, 12:06:35 PM
That engine would rev to like 5K RPM and ruin half the fun of a Miata.

?? You saying high revs are bad?
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: giant_mtb on August 11, 2017, 08:16:07 AM
Quote from: AutobahnSHO on August 11, 2017, 08:14:29 AM
?? You saying high revs are bad?

No, he's saying that such a compression ignition engine would only be able to make it to about 5k revs (think diesel), which takes half the fun (rev range) out of a normal Miata. :lol:
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: AutobahnSHO on August 11, 2017, 09:29:41 AM
Quote from: giant_mtb on August 11, 2017, 08:16:07 AM
No, he's saying that such a compression ignition engine would only be able to make it to about 5k revs (think diesel), which takes half the fun (rev range) out of a normal Miata. :lol:

Gotcha!  That would indeed suck. Nothing like revving my SHO up to 7k back when I had it. :mrcool:
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Soup DeVille on August 11, 2017, 11:54:42 AM
Quote from: giant_mtb on August 11, 2017, 08:16:07 AM
No, he's saying that such a compression ignition engine would only be able to make it to about 5k revs (think diesel), which takes half the fun (rev range) out of a normal Miata. :lol:

That may be a false assumption.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: giant_mtb on August 11, 2017, 11:55:13 AM
Quote from: Soup DeVille on August 11, 2017, 11:54:42 AM
That may be a false assumption.

Could be.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Xer0 on August 11, 2017, 03:44:28 PM
Quote from: Soup DeVille on August 11, 2017, 11:54:42 AM
That may be a false assumption.

I hope it is.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: 12,000 RPM on September 07, 2017, 12:32:24 PM
First drive :muffin: (trigger warning: Jalopnik content)

http://jalopnik.com/mazda-s-holy-grail-of-gasoline-engines-is-completely-1801820285

They really get in depth. Fascinating stuff
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: FoMoJo on September 07, 2017, 02:38:09 PM
I don't think I really want any more energy transferred to my pelvis :frown:.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Laconian on September 08, 2017, 04:25:12 AM
I love Mazda. I hope they never die.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: 68_427 on September 08, 2017, 05:01:33 AM
Quote from: MrH on August 10, 2017, 11:47:24 AM
Just imagine a 2.0 liter, making something like 170 hp, 200 lb/ft of torque, in an ND Miata, getting 55 mpg on the highway :wub:

Rumors are 187hp and 170 lb/ft
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: r0tor on September 08, 2017, 05:34:59 AM
All this tech + a supercharger... and only 187hp?  - yawn-
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: 12,000 RPM on September 08, 2017, 06:31:46 AM
It does seem to be a bit much for those numbers. VW 1.8T is not far off in fuel economy while making a buttload more torque and power.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Laconian on September 08, 2017, 06:46:00 AM
Nah. The Mazda engine looks like it'll be making in the city what VW does on the highway (38-39mpg). And it'll do on the highway what VW does... IN ITS DREAMS! (SICK BURN)
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: MX793 on September 08, 2017, 06:59:31 AM
Quote from: r0tor on September 08, 2017, 05:34:59 AM
All this tech + a supercharger... and only 187hp?  - yawn-

Probably only revs to 4000 RPM.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Laconian on September 08, 2017, 07:07:29 AM
No Y-axis, but it looks like its redline is just short of the Skyactive-G's...

(https://i.kinja-img.com/gawker-media/image/upload/agu00azixfepuceppgsw.png)
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: MX793 on September 08, 2017, 07:15:55 AM
Hmm, based on the curve shapes, I'm guessing the blower is there to help with low RPM and isn't providing much compression at higher RPM.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: MrH on September 08, 2017, 07:58:54 AM
The blower isn't really a supercharger in a conventional sense.  It's to prevent throttle loss, that's about it.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: MX793 on September 08, 2017, 08:32:24 AM
Quote from: MrH on September 08, 2017, 07:58:54 AM
The blower isn't really a supercharger in a conventional sense.  It's to prevent throttle loss, that's about it.

Odd that they'd bother with the liquid to air intercooler, then.  Just pumping air doesn't introduce the same amount of heat as actually compressing it.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: MrH on September 08, 2017, 11:42:55 AM
Yeah, I was thinking the same thing.  Maybe it's to provide a more consistent intake temperature?  The controls on this thing have to be wild.  I imagine they're trying to reduce the variables as much as possible.
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: 12,000 RPM on October 26, 2017, 09:12:10 PM
https://jalopnik.com/be-amazed-by-this-video-showing-the-inner-workings-of-m-1819890045
Title: Re: Who needs diesel? SkyActiv-X HCCI sounds awesome
Post by: Galaxy on October 28, 2017, 12:38:41 AM
The blowers primary reason is to help regulate the pressure in the engine, which would also explain why the temperature needs to be controlled.