O.S. Engine OS-18645 SPEED 91HZ-R 3D High Output Helicopter Engine  [OS-18645]

Compact Power for Serious 3D Flying

The O.S. Engine OS-18645 SPEED 91HZ-R 3D brings compact, high-output performance to RC helicopters. Its Power Boost Pipe is tuned to improve exhaust efficiency, giving sharper throttle response and stronger pull when it matters during 3D sequences.

Improved Exhaust Dynamics for Consistent Pull

By optimising how gases exit the engine, the Power Boost Pipe increases usable power across the mid and high rpm range. Pilots will notice crisper throttle transitions and a steadier feel during power-intensive maneuvers.

Engineered for Regular Use and Tuning

Built with durable components and attention to thermal stability, the SPEED 91HZ-R 3D handles the demands of frequent flying. Proper setup and routine checks will keep the engine delivering predictable performance session after session.

The O.S. SPEED 91HZ-R 3D with Power Boost Pipe is aimed at pilots who fly demanding 3D routines and need a dependable engine that responds well to aggressive inputs.