Here is the flow requirements for all four cycle engines in terms of both
cubic feet per minute and mass flow in pounds per minute to relate
to the maps in the Garrett pdf catalog. Hugh Macinnes uses
cubic feet per minute while Garrett use pounds per minute. 

The 13B rotary is indicated by the red line.

To adjust for ported side ports or the high power version of
the RX8 engine multiply the flow numbers by 1.25 to get a volumetric
efficiency of 100%.

To adjust for 2 inch diameter peripheral ports multiply the flow numbers 
by 1.5 to get a volumetric efficiency of 120%.

Incidentally there is another way of calculating the pounds per minute
of air flow if you know the fuel air ratio and the BSFC. A good double
check on what is going on.

Assume the BSFC is .47 and the fuel air ratio is 14.7 and the HP is
200. At 200 HP you will be using about 94 pounds of fuel per hour.
You will also be using 1380 pounds of air per hour or 23 pounds
of air per minute. Pretty close to the chart numbers.

Not bad for a bunch of rules of thumb assuming constant standard temperatures.
If you need it any closer than this you will have to go through
a bunch of tedious calculations outlined in the Hugh Mcinnis book
"Turbochagers" or the Garrett pdf catalog.

Paul Lamar
 
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