Date: Sat, 30 Apr 2016 22:53:23 -0400
Reply-To: James <jk_eaton@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: James <jk_eaton@HOTMAIL.COM>
Subject: Re: Friday: New VW Engine--it's Miller (cycle) time
In-Reply-To: <CACvdLxOof21pCGy1LG7zKO4umLc=GWwzW8VbDbB1h6oR4=LVrg@mail.gmail.com>
Content-Type: text/plain; charset="iso-8859-1"
Unfortunately not true - Mazda used the supercharged Miller cycle engine in the Millenia right through 2003, and now the Mazda 2 has a normally-aspirated Miller cycle engine under it's (dainty) hood.
I wouldn't compare a Miller cycle engine to a Wankel rotary at all. The Miller is an incremental improvement on the Otto cycle, not a revolution.
James
Ottawa, ON
> Date: Fri, 29 Apr 2016 09:40:30 -0700
> From: davmcneely40@GMAIL.COM
> Subject: Re: Friday: New VW Engine--it's Miller (cycle) time
> To: vanagon@GERRY.VANAGON.COM
>
> The Mazda engine could never meet emissions standards, and was dropped,
> iirc. True of their earlier rotary engine as well.
>
> On Fri, Apr 29, 2016 at 9:01 AM, Alistair Bel <albell@shaw.ca> wrote:
>
> > VW , where our heads are firmly buried in the sand.
> >
> >
> > http://www.theguardian.com/environment/2016/apr/28/vw-and-shell-try-to-block-eu-push-for-cleaner-cars
> >
> >
> > And didn't Mazda sell a Miller cycle engine in a couple of models way back
> > in the nineties?
> >
> > Alistair
> >
> >
> >
> > > On Apr 29, 2016, at 8:39 AM, Jim Felder <jim.felder@GMAIL.COM> wrote:
> > >
> > > From Gizmag.com today:
> > >
> > > Manufacturers are leaving no stone unturned in the quest to improve the
> > > efficiency of their internal combustion engines. Just this week, we've
> > seen
> > > a fastidiously engineered diesel engine
> > > <http://www.gizmag.com/ford-ecoblue-diesel-engine/43016/> from Ford
> > > and a camless
> > > engine <http://www.gizmag.com/qoros-qamfree-camless-engine/43045/> from
> > > Qoros. Now Volkswagen, no stranger to doing whatever it takes to lower
> > > consumption (figures), has joined the party by releasing a 1.5-liter
> > Miller
> > > Cycle <
> > http://www.gizmag.com/audi-high-efficiency-two-liter-engine/37428/>
> > > engine
> > > tasked with improving fuel consumption and increasing low-down torque.
> > >
> > > Volkswagen's engineers say there are a number of improvements that come
> > > courtesy of the improved thermodynamic efficiency associated with Miller
> > > Cycle engines. An increase in the geometric compression ratio has,
> > > according to VW, allowed for improved efficiency in the load range most
> > > customers will actually use, while the final compression temperature has
> > > been lowered through early closing of the intake valve and the expansion
> > > cooling that brings.
> > >
> > > Thanks to these improvements, VW claims its new engine offers up peak
> > > torque from just 1,300 rpm, while also improving fuel economy by 1 l/100
> > km
> > > (235 US MPG) compared to the current 1.5-liter TSI engine.
> > >
> > > Working tandem with these big changes to the combustion cycle are a
> > number
> > > of small changes that, when combined, contribute to the longevity and
> > > efficiency of the engine. On the 110 kW (148 hp) version of the engine,
> > the
> > > cylinder liners are coated with an atmospheric plasma spray to cut down
> > on
> > > friction, improve heat dissipation and improve corrosion resistance.
> > >
> > > The engine's cooling system has also come under the microscope, and now
> > > will make sure the water in the crankcase and engine remains stationary
> > > while the car is warming up. As well as cutting the amount of time spent
> > > without the engine operating at ideal temperature, VW says the system
> > helps
> > > warm the cabin more quickly on cold mornings.
> > >
> > > Although it's usually used on high end, big displacement engines, VW has
> > > even fitted cylinder deactivation to the new engine, allowing it to run
> > as
> > > a two-cylinder under light loads.
> > >
> > > An increasing injection pressure 350 bar has improved the mixture
> > formation
> > > in the engine, which should also lead to lower particulate emissions.
> > >
> > > Interestingly, the release makes it very clear the efficiency and
> > emissions
> > > improvements are unlikely to show up under test cycle conditions, but
> > > argues that they're likely to have a "distinct impact on the customer's
> > > everyday driving."
> > >
> > > The new four-cylinder engine will find its way into showrooms later this
> > > year in 96 kW (129 hp) and 110 kW (148 hp) guises. It's currently on show
> > > at the Vienna Motor Symposium.
> >
| 
