Scott Speirer wrote:

Paul,

Thought I'd bounce my turbo matching estimates off the readership for any possible
feedback.  I am assuming a stock 13B turbo with intake and exhaust manifolds that
provide the same airflow behavior/efficiency as the RX-7 car manifolds.  No power
beyond that of the stock version is expected, just normalization of the power up to
15,000 feet density altitude.  (e.i., a critical altitude of 15,000 ft.)  This is
based off of the method in "Turbochargers", by Hugh MacInnes.

For the purpose of airflow calculations as a function of engine rpm, the engine has a
displacement of 2600 cc's.  This converts to 158.6 cu in.  (Paul - thanks for this
info.)

Russell Kent wrote:

Uh, each rotor has an effective displacement of ~650 cc per e-shaft revolution.  That's 1.3
liters (and thus the name 13B, or 20B for a 3-rotor).  Why did you double this to 2.6
liters ?  I think this will cause some of your calculations to be off by a factor of 2x.

Russell Kent

At my suggestion Russell. The rotary pumps the same amount of air
as a 1.3 L two cycle or a 2.6 liter four cycle. We went around and
around about this well over a year ago. Basically what is happening is
the wankel rotary pumps air like a two cycle but it is really a four cycle
engine. Amazing no? One of the reasons it is so small and light for its
HP. This is also why racing organizations rate it as 2.6 L when racing
against four cycle piston engines.

Paul Lamar

Ah yes.  I know about the displacement wars.  :-)
I understand now.  Thanks.

Russell Kent

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