Re: rotary reciprocating engines - how smooth they are

[ChrisBourk@xxxxxxx]

<< I think most people just listen to the "music" of the engine and can
tell that it's time to shift.  As I understand the RX7 rotary engine,
you need that warning tone to tell you that you're zipping past 10k
RPMs and that the streams will soon be crossed and everything nearby
will soon undergo total protonic reversal, even though it still sounds
about the same.  Is that not true?>>

Actually the rotary engine isn't all that different from a regular piston
engine - BOTH are reciprocating.  Think of the Mazda 12A/13B engines as a 6
cylinder engine (2, 3 sided rotors).  Their rociprocating parts are the rotors
which swing around an excentric shaft and follow the shape of an epitriquoid
(sic) as one of the 3 sides of the rotor sweeps through the compression stroke
(rotory engines are 4 cycle as well) the rotor stops moving in one direction
(although it keeps moving) and reverses going back in the oposite direction -
in that way it is no different that a BMW piston engine.  

I've never worked out what in a piston engine would be the connecting rod to
crankshaft ratio  for the rotary engine but I'd guess it is mutch less
stressfull than a normal piston engine.

I studied the Wankel engine at length before installing one in a '70 911 I
had.  After seeing it was good enough for MB to build the C111 car with I
figured I'd giver it a try.  These engines are truly GREAT! I remember a fella
who used to set a "redline light" to come ON if his tech went BELOW 8,000 rpm
when shifting.  This is how he knew to downshift :)

As a historical note - almost every car manufacturer on the planet bought the
rights to build the engine from Felix Wankel but it was Mazda who discovered
the side intake ports making the engine drivable below 3,000 rpm.  Poor MB
they only built 3 and 4 rotor cars - how I would like to have one of those
now...

Best regards,

Christopher
A couple of BMWs with old fashioned piston engines...

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