Still suitable for aircraft however as prop HP required is = to RPM^3 X
Constant
Actually a road race engine requires a broader torque curve than an
aircraft engine.
Your curves also dispute your claims that the Wankel is not
breathing limited. the torque curve of an imaginary engine that
is not breathing limited would proceed past the torque "peak"
at a constant level - which these obviously do not,
Not true. All you do is change the pipe length as a function of
RPM which is exactly what Mazda did.
The fall off
of peak torque with the move up the rpm range does not indicate
improved breathing, but a reduced filling of the chambers at the
new peak in spite of the resonant amplification of the tuned
intake. BMEP numbers for the typical Wankel engine actually
suggest that Wankel port breathing is less effective than well
designed poppet valves and cam.
That is only true of you use your erroneous numbers for displacement.
You must be kidding about the archaic poppet valves.
Look at the pictures. Is there any silly poppet valves in the
way. Heck a person could put their fist into a Lemans engine
through the intake port.
The high volumetric efficiencies
quoted for Wankels are not supported by BMEP numbers
There is no data that suggests that a 13b is capable of 240
at 6000 rpm with normally aspiration and normal fuel.
Yes there is. Cut a four rotor in half and you have a 240 HP
two rotor at 6000 RPM.
The Lemans engine had to run on automotive pump fuel and not nitromethane,
alcohol or any other kind of racing fuel. Those are the rules.
Name another 2.6 L N.A. street engine generating 250 HP like the RX8.
I do not think even the Le Mans engine makes 120bhp
per rotor at 6000 rpm, and 13B's are a lot further from that
engine than reworked ports.
Vance
It sure does make 120 HP per rotor at 6000 RPM. There is no fundamental
difference
in the Lemans engine from your typical 13B engine that would limit
the power at 6000 RPM. Larger P ports are available from Racing Beat than
even
the Lemans engine P ports. The main difference was rotor weight and
that would only affect top RPM. The RX8 probably has the same weight rotor
as the Lemans engine.
Yes - the Le Mans is on the pipe by 6000 rpm and is seeing at least 3 psi
resonant boost
and slightly exceeds 120 per rotor.
Now for Combustion engine 101
I did not use any "bogus displacement for the bmep calculations. The purest
way to
compute BMEP is to establish the number of power expansions in one minute
for
the selected operating point and multiply this by the swept volume of each
of
those power "strokes". using cubic inches since we are seeking a psi. Then
compute the total work during this minute using either torque or horsepower.
Convert that work into pound inches for dimensional consitancy, and divied
that
work by the total volume. (does not matter if it is rotors, pistons, 4
stroke, or two
stroke). BMEP is one of the most accepted measure of engine efficiency being
a measure primarily of volumetric efficiency and compression ratio.
BMEP is maximum at peak torque since that represents the best filling of the
chambers
and of course, it is modified by "boost - super charging".Some values at
peak torque
for familiar engines
RX8 150.2
Chevy truck 157.3 pushrod 2 valves low comp ratio
Cont IO-360 171 pushrod 2 valves low comp ratio - but some resonant
boost
Hyundia 163
NissanMX 180
Le Mans 211 full race engine - over 3 psi resonant boost
Ferrari 200 advanced street engine
And you do not want to even see what a stock 13B does. Vance
Your right! I give up! The engine is a shitty 4 liter engine. No more use
in aircraft. The BMEP is not up to piston engine standards. Besides all that
it is missing a bunch of essential parts like pistons, crankshafts and poppet valves.
No way will the FAA ever certify a rotary.
I only ask one thing Vance. I want you to send me a messages stating
unequivocally, without if ands or buts, that the 13B is an 80 cubic inch
displacement engine.
Paul Lamar
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