> > > > > Jerry Hey wrote:
> > >> >
> > >> > I think that my wife, Joy, has determined the
peripheral port size
> > >> > and timing of the Leman Engine. Here is what we did. First I
> > >> > measured the inside vertical height of a l3B rotor
housing. This I
> > >> > determined to be 9.44 inches which we divided in two
(4.72")since we
> > >> > were only interested in the top half where the intake
port is. Now I
> > >> > step out of the picture and Joy takes over. The second
step was to
> > >> > import the drawing of the Leman engine into PhotoShop where it was
> > >> > cropped to eliminate all but the top half of the rotor
housing. This
> > >> > was saved as an EPS and exported to PageMaker. Then, in PageMaker
> > >> > she drew a line 4.72" long and scaled the eps image so that the
> > >> > inside top of the rotor housing and the horizontal center line
> > >> > matched up with the ends of the 4.72 line. At this
point the Leman
> > >> > drawing was at one to one. Then, using Pagemaker tools, Joy
> > >> > measured from the center line to the bottom and top of
the P Port.
> > >> > It was 1.2" to the bottom and 3.188 inches to the top.
That is close
> > >> > enough to use a 2"i.d. x 2.25 o.d. aluminum tube for the
insert. The
> > >> > runners appear to be same diameter as the port.
> > >> >
> > >> > Don't know what I'd do without her. Jerry
> > >
> > >> Jerry, I'm be very interested in your progress. Please let me
> > >>know how your doing the PPorting.
> > >> IE, Mill or die grinder. Will you have the port set at an
> > >>angle like Power Sport does? Are
> > > > you going to thread the insert? Any help here is
appreciated. Tom Webber.
> >
> > Tom, The P-Ports will be NC milled. I don't think it is necessary
> > to thread the insert although this is what Jim Mederer says. I know
> > that others have not threaded and have not had problems. The angle
> > of the insert is another question. I would prefer it to be
> > perpendicular to the housing. However, this places the runner at a
> > weird angle if you intend to go over the top of engine. Better to
> > just have a couple of 90 degree bends that can be readily bought. I
> > am not locked into anything yet. The P-Port timing is still a
> > mystery to me. I tried to compare Paul Yaw's numbers with the tech
> > drawing of the Leman ports and they did not coincide. Maybe I did it
> > wrong. I would be happy to just copy the Power Sport ports, if
> > only I could. Jerry
> > --
> > Jerry Hey
> >
> > Tailwind & Rotary Engine Support
> >
> > http://www.j-winddesigns.com
> >
> > mailto:j-winddesigns@thegrid.net
>
> Jerry, you got the dimensions on the Leman engine. Why don't
> > you just copy that? What do you need the timing numbers for?
> > They are just academic anyway. If the port is in such and such
> > a location the timing is such and such. The two things are inextricably
> linked. I can't figure out what it is you are missing?
> There is no cam shaft timing to be set. There are no cam lobes
> to clock.
>
> Paul Lamar
Jerry,
The Le Mans inlet port has the following timing:
IO 1.2" = 30.5 mm = 102 degrees BTDC
IC 3.188" = 81 mm = 74 (73.8) degrees ABDC
With reference to a piston engine:
IO = 68 degrees BTDC
IC = 49.2 degrees ABDC
The housing dimensions are short axis = 180 mm, long axis = 240 mm.
housing width = 80 mm.
For convenience, see attached pic.
Regards
Rolf Pfeiffer
We sent this before Jerry. Did you not get it?
Paul Lamar
Yes, I got it. It uses the data points that Joy generated from the
Jpeg. It does not verify them as correct.
Jerry Hey
Tailwind & Rotary Engine Support
http://www.j-winddesigns.com
mailto:j-winddesigns@thegrid.net
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