Rotax 532, 582

Although the EFS-2R is no longer in production, we continue to get questions about it.   We are including this page to provide some information about it's Rotax 532 application.

Rotax 532

Because two cycle engines require a very rich fuel mixture to keep the engine from over heating, the fuel consumption of the 532 at sea level with the EFS-2R installed, is about the same as with the Bing carburetors.  However, if one were to take off at sea level and cruise at high altitude, then the EFS-2R should provide a fuel savings as well as better engine performance because the mixture at altitude can be adjusted in flight.  Our tests indicate that the installation of the EFS-2R caused about a 4 HP penalty in engine power at sea level but the penalty disappeared at 4000 feet and becames a power benefit at higher altitudes.  This power comparison was made by testing properly adjusted Bing carbs, followed immediately by tests of a properly adjusted EFS-2R.  Because of constant changes in atmospheric conditions, a set up of Bing carburetors that is optimized one day is unlikely to deliver peak power the next day.  Therefore a power comparison with the EFS-2R conducted a couple of days after the Bings have been adjusted will indicate a much smaller or non-existent power penalty.

Rotax 582

Having have never tested the EFS-2R on the Rotax 582, we cannot recommend it's use in that application.  Because of internal fuel flow limits in the EFS-2R, it is very likely that it's fuel flow rate would be inadequate for that larger engine.