O.S. Engine 91RZ-H Rear Exhaust Ringed Heli Engine  [OSMG1978]

Terrific news for your heli modelers: the popular and powerful .91 ringed engine now comes in a rear-exhaust design!

Pilots of Hirobo and other scale machines will appreciate how the 91RZ-H power plant will fit inside the canopy to preserve the heli's scale lines.

Like the side-exhaust 91SZ-H, the 91RZ-H features new intake porting, new carb and a redesigned crankcase that offers better support for the crank and thrust bearings.

Available with two heat sink heads: a larger, blue anodized head for more efficient cooling or a more compact, squared die-cast head (DH).

SPECIFICATIONS

• Stock Numbers: OSMG1978 91RZ-H
• Displacement: 0.91 cu in (15 cc)
• Bore: 1.09 in (27.7 mm)
• Stroke: 0.98 in (24.8 mm)
• Practical rpm: 2,000-16,000
• Output: 3.3 hp @ 15,000 rpm
• Weight w/o muffler: 21.3 oz (605 g)
• Includes: #8 glow plug