George and Jerry,
I believe that a properly contoured 1-3/4" port will work fine, but I
believe that the tube length is far more important. My logic is that
smaller ports do incur more pumping losses. Another thing to remember is that if
your engine makes more power than you expect at a predetermined RPM that is OK
too. I completely understand why you want to go with 1-3/4" (44.5 mm George) to
keep the gas flow speeds up. The thing to remember is a badly contoured or
poorly timed small port will insure nither power or tractability. What really
needs to happen is we need to build some of these things and test them.
George,
I have e-mailed Larry through the other list. I can't help him unless
he contacts me. So far no joy. I have some ideas for products which I would
contribute just for the parts if he is willing to cooperate I'm in.
Bill Jepson
Jerry,
I am totally in agreement with your on this subject Jerry and I
would dearly
love to get Larry (on the other list) who is an engineer with
his own CNC
engineering business, on this list as well. Now Larry gave
a really good
evaluation/assessment on the port sizing which was in line
with all that I'd
see before and he concluded a smaller Diameter PP which
someone didn't agree
with - Jerry and I have both asked for his e-mail
address and it never found
the group ( funny that).
I was hoping Bill
J. would be able to arrange this ( hint, hint).
BTW Larry is intending to
manufacture Mazda components, to service the
Aviation Industry. Just reading
his suggestions, convinces me he knows what
he's about in relation to the
rotary and is in a position to be a great
contributor. However I did suggest
he make single cranks but I got no
response from that one.
Now the
suggestion of welding a SS tube to the steel liner ( on the inside)
and my
suggestion to Bill J. of an O ring on the outside, would seem to me
to be
the ideal PP configuration, now the only other thing to decide is the
Diameter. I believe 1.5" ( 38mm) is adequate, but with any restriction
maybe 1.6 ( 40 to 41mm) to 1.7 ( 43mm) would be necessary. I think the
suggested Al 2" ( 51mm) has an ID of 1.8 ( 45-46mm) - we really are
splitting hairs at this stage.