Date: Thu, 8 Mar 2018 11:09:43 -0600
Reply-To: KI4TLF <ki4tlf@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: KI4TLF <ki4tlf@GMAIL.COM>
Subject: Re: Is THIS the "boxer" transplant we've been waiting for?
In-Reply-To: <CAFnDXk0Kfx8y1Tf4BWMZ_zCQ6Y8JJuETxNeP0TgpDqLtC_JJyQ@mail.gmail.com>
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If it's like most 2 strokes, you have different port timing for the intake and exhaust depending on the rotation. The most efficient port timing in one direction would not be most efficient for a reversed direction. Identical timing is not the most efficient for either direction.
GregM
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Jim. Felder
Sent: Thursday, March 08, 2018 7:33 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Is THIS the "boxer" transplant we've been waiting for?
Raimund, that's an interesting observation. You might have to turn the rods around so the pistons face the other way to do that. I piston engines there is (always, usually?) a very slight offset on wrist pins so that the compression, combined with the dynamics of the moving piston and rotating crankshaft, even out the loads on the piston in the cylinder bore.
On Thu, Mar 8, 2018 at 7:27 AM Raimund Feussner <ray@v6bus.de> wrote:
> The adjusting valves would disappear.
>
> So how can you control intake/outtake strokes? You would need to
> modify the position of the opposing pistons to each other, maybe.
> That´s why I thought of the tensioner. Like on Audi twin camshaft
> heads, which use an oilpressure controlled tensioner (adjusting intake to outlet camshaft).
>
> David, I mean the ugly gear connecting both cranks...
> The flywheel is only on the lower crank.
>
> However, since it´s a two stroke without camshafts, running it
> backwards just needs a reversed starter motor.
> Perfect for front-engine setups in rear-engine cars! The solution to
> all our problems!
>
> Raimund
>
> Am 07.03.2018 um 22:10 schrieb Jim. Felder:
> > I was thinking same as Raymond, that the moving parts in an OHV
> > engine
> are
> > a lot of both the energy and manufacturing inefficiency of a
> > traditional engine. I don't think a belt or anything else would work
> > though, and
> what's
> > an extra gear or two? Transmissions are full of them, no problem really.
> > The configuration shown in the video is probably not going to be the
> > end
> of
> > the story if this design gets beyond the test bed stage and the best
> > mechanical and manufacturing minds start pondering it. The only
> concession
> > to precision control mentioned in the video seems to be the boost,
> > so I
> am
> > not sure variable piston relationships would be needed if that is so.
> >
> > Emissions? Don't know but it seems like 45% efficiency would be a
> > great place to start from.
> >
> > Jim
> >
> > On Wed, Mar 7, 2018 at 2:18 PM Alistair Bell <albell@shaw.ca> wrote:
> >
> >> Bah humbug
> >>
> >> Just an updated and trimmed down version of Napier Deltic.
> >>
> >> :-)
> >>
> >> Alistair
> >>
> >>
> >>> On Mar 7, 2018, at 8:48 AM, Jim. Felder <jim.felder@GMAIL.COM> wrote:
> >>>
> >>> Everything is wrong with this new engine--opposed piston,
> >>> combustion ignition, two-cycle. But check out the video and tell
> >>> me--if it became popular—that you wouldn't want one in your Vanagon.
> >>>
> >>> <
> >>>
> >>
> https://www.cnet.com/roadshow/videos/radical-new-engine-makes-a-run-at
> -reality/?ftag=ACQ-00-10aaa5b&vndid=00e8ca988f7d01a748f9a28d57d69900d7
> >>> Jim
> >>
>
>
