Another step in the right direction.

In deciding which way to go with the intake for the single rotor, I ran
two tests. The first one with a short 8" long intake runner, and a
second one with a 24" runner.
The results are certainly not surprising, however, I had to check the
possible impact on idle characteristic.
Except for a different idle mixture setting, I was not able to detect a
difference in idle characteristics at 2000RPM. There is no need for
lower idle with a 3.33 : 1 gear ratio. If for any reason I want to go
lower with idle, I would have to increase the fly wheel inertia. With no
load on the engine it idles down to 1300RPM with the 8" runner.
The long runner also resulted in a 1" higher MAP over the short runner.

The 24" runner as shown in the picture will in the final configuration
be at least 3" longer, because the carb has to com lower than it is now.

The engine config is 12A rotor and housing using 1 1/2" p-port.

The HP calculation is based on a bsfc of .5 . This is probably
conservative with EGT at 1700F and mixture ratio at 14.6 .

Richard Sohn
N2071U

 Way to go Richard. Confirms out tuning results with other p-port engines.

Paul Lamar