O.S. GT33 Gasoline Engine

Second in the line of O.S. gasoline engines — but second to none in quality and performance!

When it comes to gasoline aircraft engines, the GT33 is in a class of its own. It has the muscle to swing larger props, and it stands out for many other reasons, too. The GT33 runs more quietly than comparable engines while exceeding their output, and it starts easily with electronic ignition that accepts many battery types. Once again O.S. has produced a gasoline powerhouse for the serious pilot!
Displacement: 2.013 cu in (32.98 cc) Bore: 1.417 in (36.0 mm) Stroke: 1.276 in (32.4 mm) Practical rpm: 1,800-8,000 Output: 3.85 hp @ 9,000 rpm Engine: 34.72 oz (984 g) Silencer: 5.65 (160 g) Igniter: 3.70 oz (105 g) Includes: engine, E-5030 muffler, ignition module, CM-6 spark plug, exhaust gasket Requires: gasoline, 2-cycle oil Recommended props: 18x8, 18x10, 18x11, 18x12, 19x10, 20x8, 20x9, 20x10 Suggested Break-In Prop: 18x8 Ignition Battery: 4.8-6.0V NiCd or NiMH, 6.6V LiFe or 7.4V LiPo pack Gasoline/Oil Mix: 30:1-50:1
  • Produces 10% more power than any other engine in its class!
  • Electronic ignition system offers fast, easy starting — and accepts LiFe, LiPo, NiCd and NiMH power.
  • Rear-mounted Walbro® carb and intake simplify mounting and installation.
  • O.S. E-5030 muffler effectively controls exhaust noise without compromising performance.
  • Includes Rcexl spark plug.
Ignition Module
Enjoy quick, confident starts with the included ignition module — which accepts batteries of all types, including LiFe and LiPo chemistries.
With other engines you have to purchase a Pitts-style muffler separately — but the GT33 comes with an E-5030 muffler that resists distortion, resulting in 5dB less noise than similar engines. The space-saving design reduces the need to cut the cowl in order to fit in scale applications.
Mounting Walbro Carb
Mounting the Walbro carb at the rear allows for easy installation and easy needle access. The backplate mount is designed to reduce vibration, and the carb features a factory-supplied choke linkage, which needs to be set up by the modeler.
Crankshaft and Bearing
Crankshaft/bearings, piston liner and piston/pin and rod for the GT33.
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