Nick,


Comparative engine tests performed by someone that can be considered biased toward one of the competitors, are not regarded as objective...
...So, I will not buy any OS engine to compare to the MVVS...

It is true; before you operate the MVVS .91/15 cc engine, you can undo the bolts that connect the cylinder casing to the crankcase, carefully release the bond between the two parts (taking care not to bend the con-rod) and reinstall it in a rear-exhaust configuration, or with the exhaust on the other side.


Even more so than the OS.91FX, which has a 17 mm crankshaft, the MVVS has a 15 mm crankshaft, which is even more biased toward lower RPM torque and spinning large propellers. This is through harnessing high flow speed, which increases low RPM cylinder charging, rather than high flow, which increases high RPM power.

The target is retaining flying fields, in this day and era, where high RPM will do more harm than good, by making a noise than non-R/C people consider more offensive.


...And even then, the HP claims that you stated are more nonsensical then ever...

Go to [link=http://www.jettengineering.com]Jett Engineering[/link] and use the PropPower to calculate the horsepower from their guaranteed RPM data for their very high performance .91 engines. ...And Jett engines are more powerful than OS...