I am stuck on 1 7/8 runners. Sames as the Lemans engine.
Why reinvent the wheel. I know it rolls :)

Paul Lamar ...No rotor no motor.

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Hi Paul,
I can't find my torque/power figures for the LeMans engine; what rpm
was it getting max figures at?
I'm thinking 1.75 in runners might suit our rpm better.
Ta, Dave McC

There is a big difference in the port area.
1.75 OD is  is really 1.625 ID. Area is 2.07 square inches.
2 inches OD is 1.875 ID. Area is 2.76 square inches.
My guess is HP would be less than 200.

Here are the Lemans curves.