> > > > >Jerry Hey wrote:
>> > >>
>> > >> Paul, how about designing the pp intake system for me and all
>> the
>> > >> other guys who are thinking about it. I think we should come
>> very
>> > >> close to Power Sport's design. Could we use your intake
>> parts
>> > >> for the cold side stuff? They are 1.5o.d. which is what I was
>> > >> thinking of for the i.d. port size which I got from your drawing
>> on
>> > >> the ACRE site. If we can match these (or do they need to be
>> > >> matched?) that would make it a lot easier. And look good, too.
>> > >>
>> > >> Maybe we can find a throttle body that was used on a production
>> car.
>> > >> New, high performance throttle bodies that I have looked at on
>> the
>> > >> internet are expensive.
>> > >>
>> > >> I will commit myself right now to providing housing machining and
>> the
>> > >> inserts unless someone else wants to do it.
>> > >>
>> > >> Jerry
>> > >>
>> > >> p.s. The first structural change to the Tailwind caused by
>> rotary
>> > >> performance is a thicker windshield.
>>
>> > >If I were doing it I would copy the Leman engine porting exactly
>> > >except put the butterflies next to the rotor housing.
>> > >240 HP at 6000 RPM and a lot more at 7500 with a 2.85:1 PSRU.
>> > >You don't need a throttle body. Just a couple of home made
>> > >butterflies. You also don't need my castings as everything is
>> > >too simple and can be made from tubing. Scale up this
>> > >drawing for the same size tubing Mazda used on the Leman
>> > >engine.
>> > >
>> > >Thicker Windshields are a good idea anyway. That reminds me
>> > >I need to get one for the KIS.
>> > >
>> > >Paul Lamar
>> >
>> > Do the home made butterflies need bearings, seals, return springs,
>> > throttle position sensors? Am I making this too complicated? Jerry
>>
>> You don't need throttle position but some small SS shielded flange
>> ball bearings would be nice. You can get these from:
>> W.M. Berg
>> Stock Drive Products
>> Sterling Instruments.
>>
>> I think I have some quarter inch versions lying around I can send
>> you.
>>
>> Paul Lamar
>
>
>> Looks like the same bearing used in roller blade wheels.
>>
>> T. Webber
>
>Godd source :-)
>
>Paul Lamar
OK. I will take a shot at making the butterflies. One last thing:
in the drawing you sent of the Everett Hatch Style ports, the bore
of the section that is inserted is less than the bore that contains
the butterfly. Is this necessary? What is the smaller bore?
Could one use a 2" o.d. x 1.75" bore for the whole thing? Jerry
Not clear form the drawing put the part than goes in the housing
is square.
You would not get as much power as the Leman engine.
But if that is OK go for the 1.75" bore. If it were me I would go
for a two inch bore and 2.25 OD tubeing. Why mess around? You are
going to cut holes in rotor housings anyway.
Are you going to start with new housings?
The area differnce is:
A 1.75 inch bore = 2.4 square inches.
While a 2 inch bore would be 3.14 square inches.
30% more area.
Paul Lamar
Jerry Hey wrote:
How does bore size relate to fuel consumption, idle smoothness and
so on.? Can hp at 6000 rpm be predicted for various bore sizes?
I have no idea. We can test for some of those things on the dyno
when you get it built.
Paul Lamar
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