Im thinking the 25 would be a minimum on a Classic 200 Opti setup. My PII came with a 25 and I am now running a 27 Tempest on my 200 Opti. I would think this would be more in the pitch range you should be looking at. 26 Trophy or 27 Tempest maybe. With these two props you should see close to mid 70s once you get it setup and can drive it. I cant imagine running a 25 or 24 pitch on that rig and not getting into the limiter.
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