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

Sorry - While I will gladly state that the Wankel is a fine, inovative
engine with
amazing packaging size for the swept volume, and will make a very
satisfactury
aircraft power plant (especially with it's robust construction and reduced
catastrophic failure modes) - you will see an evil looking fellow with horns
and tail
lining up to buy long johns and down jackets - before I agree that it is an
1.3 liter
engine. Although I am a firm advocate of truth and honesty in engineering, I
have
to admit the fact that Mazda is continuing to screw the Japanese tax man
does not upset me. Vance Jaqua

You must have read my mind. I was about to get on your case. Then you
must also admit your bogus (your word) BMEP calculations are based on your  
over estimated bogus displacement :)

You also failed to answer 50% of the exam so you get an F. I will up your
grade to a C - and give you another chance to answer the last question.
Name another 2.6 L street engine that gets 250 HP like the RX8 engine
does? 

BTW H. Heisler in his book Advanced Engine Tech also disagrees
with you. He states it is equivalent to a two cylinder four cycle
engine of twice the displacement. Just like a two cycle is equivalent to
a four cycle of twice the displacement. You are out of sync with the world
on this point alone Vance :)


Paul Lamar
 
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