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Instruction Manuals:	Manual 1 (425 KB)
Tower Catalog Page:	199

           This is the O.S. Max .21 VZ-R, 7-port engine Version 2.
             Created Expressly for 1/8 Scale On-Road Competition.
               This Racing Engine DOES NOT Include Any Warranty.

FEATURES: An improved internal crankcase core and re-shaped liner port for
               better mixture flow
          A button-shaped inner head design to boost high-end rpm
          A piston machined from bar stock for more strength
          More crankcase webbing helps the engine cool better and adds
            structural strength
          Rear exhaust port is cast as part of the cylinder to improve exhaust
            flow
          2-piece turbo cylinder head is designed specifically to work with the
            new high-performance T-P7 Turbo Plug
          Oversized blue anodized cylinder head for more cooling
          True ABC construction (Aluminum Piston with a Chromed Brass Cylinder)
            reduces break-in time. The lightened piston improves cooling and
            acceleration. Con rod has lighter, more durable bushing material
          Universal fuel inlet nipple can be repositioned for better access
          Needle valve assembly is encased in a protective sleeve
          Dual crankshaft bearings.
          Full linear action of a 20K Slide Valve Carb, for more consistent
          throttle response throughout the RPM range
          Carburetor stop valve prevents the rotor from sliding too far
          Crankcase backplate has an O-ring for a better seal
          Pilot shaft crankshaft

INCLUDES: One .21 VZ-R VER. 2 engine with 20K Slide Valve Carburetor
          One P7 glow plug
          One Head Gasket
          Three dust caps
          One instruction manual and decal sheet
          One rubber exhaust seal

REQUIRES: Glow Fuel: 5%-30% Nitromethane (10% Recommended) with an oil content
            16% or more.
          Manifold (Header)
          Silicone coupler
          Tuned pipe or muffler

SPECS:    Displacement:           3.5cc (.211 cu in)
          Bore:                   16.6mm (.654")
          Stroke:                 16.0mm (.630")
          Power Output:           2.5 BHP at 34,000 RPM
          Practical RPM Range:    3,000 - 42,000 RPM
          Crankshaft Thread Size: 1/4-28
          Weight:                 315.5g (11.1oz)
                  Mounting Dimensions:
          Distance between mounting holes on same side:       0.83" (21mm)
          Distance between mounting holes on opposite side:   1.46" (37mm)
          Width of engine at cylinder head:                   1.95  (49.6mm)
          Width of crankcase neglecting mounting flanges:     1.21" (30.8mm)
          Width of crankcase with mounting flanges:           1.77" (45mm)

          Length from center of engine to end of crankshaft:   2.89" (73.5mm)
          Height/crankcase bottom to top of cylinder head:     3.9"  (99.5mm)
          Height/bottom of mounting ears/top of cylinder head: 3.3"  (84mm)

          NEEDLE SETTINGS: These are pre-set from the factory and require
            little or no adjustment
          High Speed - 3 turns out from fully closed
          Throttle Stop Screw - .5 - 1mm out from fully closed
          Mixture Control Valve (low speed) - Flush with ball link/carb body

COMMENTS: This engine uses only O.S. Turbo Plugs.

                                                                   ajw 05-22-04
                                                           Updated: EEW 8/10/04
                                                           Updated: JBM 4/25/06
                                                                         ir/jxs
                                                               updt lmm 4/14/09



– If you need more information, use these O.S. resources –

Click Here: Manufacturer's Product Web Page
E-mail: enginesupport@hobbico.com
Web Site: http://www.osengines.com/
Phone: 217-398-8970


 
Postal Address:
O.S.
3002 N. APOLLO DRIVE, SUITE #1
CHAMPAIGN, IL 61822  








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