Get a bag of popcorn



Place the 13B housing on a table.



Put the rotor in the housing with one of the apex seals pointing to a major
axis.



The maximum displacement is then obvious on the opposite side.



Fill the maximum displacement cavity with popcorn and level the top.



Remove the popcorn and dump it into an empty square milk container.



Measure the width and height of the popcorn and you will find it shows a
displacement of 13.33 cubic inches. Multiply this number times three and you
will find that we have a forty cubic inch displacement in each rotor of the
13B engine.



A single rotor Wankel engine compares with a three cylinder four cycle
internal combustion engine as it fires twice for every drive shaft
revolution.



A double rotor Wankel engine compares with a six cylinder four cycle
internal combustion engine as it fires twice for every drive shaft
revolution.

Kenneth McKenzie

Sorry Ken. No cigar. The engine is equivalent to a  2.6L four cylinder
four cycle piston engine  and it fires twice per rev.

As piston six fires three times per rev.

Study these charts again.