While a carb probably damps that organ pipe effect, doesn't the
   configuration of the airbox (plenum) on the cold side of the carb come
   into play?  So, the hot side of the manifold is very short, the cold
   side is often quite a bit longer...


   Regards,

   Matt-

Matt,
This is a correct statement, but... The max power is usually made at
wide open throttle. The most modern carbs have streamlined throats. They
are called smoothbores. Minimal obstruction of the tuning effect. The
carbs have short velocity stacks adding less than 1-1/2 inches. So the
pre carb length is also very short. The plenum, is as large as possible.
The plenum is also setup to be pressurized by ram air. It is effective,
I have taken the ram tubes off and there is a significant loss of power.
No easy way to dyno this but I had to jet down 1 main jet size. The
rotary is an unusual animal due to the port intakes. The rotary reacts
more like a 2 cycle. Lynn has laid out a batch of suggestions of how the
intake and exhaust interact. I worked on an RX-2 sedan racer in the days
before muffling was required. This car is probably why race tracks now
require some muffling! The exhaust was two short slightly diverging
tubes into a collector and that was followed with a long diverging
megaphone that exited under the right door. The ported exhaust was so
loud that it actually hurt, wearing ear plugs AND earmuffs. A reasonable
length intake is probablyat least 12" long for better performance. As
Lynn mentioned it needs to be well made as a perfect length intake that
is poorly made won't work any better. A saying I used to use with
customers is, "Everything effects everything else." This sounds kinda
silly, but it's really true. You can't port your rotary and just expect
more power without intake and exhaust changes as well.
Bill Jepson



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