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osspeed21vzbspecii

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OS SPEED 21VZ-B Spec II

This is the 2008-2009 Worlds Edition.

OS Speed 21VZ-B Spec II

Specifications

Variant
Manufacturer OS Engines
Re-branded Engine No
Brand OS Speed
Model 21VZ-B Spec II
Evolution of OS Speed 21VZ-B V-Spec
Part # 13911
MSRP $399.99
Bore 16.6mm / 0.654in
Stroke 16.0mm / 0.630in
Displacement 3.46cc/0.211cu in
Weight 349g/12.32oz
Instruction Manual Click
Exploded View Click

Crank Specifications

Variant
Crankshaft Double Tungsten Slugged/DLC Coated/Silicone Fill
Crank Type 14mm SG Style

Crankcase Specifications

Variant
Rear Bearing Ceramic 14.00 x 25.40 x 6.00
Front Bearing Steel 7.00 x 19.00 x 6.00
Case Cast Aluminum Black Oxide Coated
Backplate Bump Start

Rod Specifications

Variant
Rod Knife edged Aluminum with brass bushing
Rod Length 30mm

Piston/Sleeve Specifications

Variant
Piston/Sleeve Type ABC(Aluminum Piston, Brass sleeve, Chrome Liner)
Intake Ports 3
Exhaust Ports 1

Carburetor Specifications

Uses OS 21J carburetor. Carb Needle settings are default after breakin.

Variant
Carburetor OS 21J
Carburetor Size 7mm
Carburetor Style Slide
Carburetor Material Aluminum Body with Nylon insulator
Carburetor Adjustment 3 Needle
Carburetor Restrictors 6mm, 6.5mm, 7mm
Carb LSN -
Carb MSN -
Carb HSN -

Head Button/Cooling Head Specifications

nitroenginewiki.com_images_osspeed13911_coolinghead.jpg

Variant
Head Button Turbo
Supplied Glow Plug OS P3
Cooling Head Black Anodized Drilled Aluminium

Timing Specs

Intake Rotor Timing Opening 15.5° ABDC
Intake Rotor Timing Closing 74.5° ATDC
Intake Rotor Timing Duration 239°
Transfer Timing Height 3.5mm from BDC
Transfer Timing Duration 114°
Exhaust Timing Height 6.4mm from BDC
Exhaust Timing Duration 114°

TIMING DIAGRAM HERE

Performance

Manufacturer Claimed Peak 2.5ps @ 34,000
X-Dyno Peak Power(HP) 1.5 @ 26,000
X-Dyno Peak Torque(oz-in) 59.82 @ 25,000
X-Dyno Peak RPM Measured 42,750

nitroenginewiki.com_images_ptk2500_xdyno.jpg

Variants

Variant
OS Speed 21VZ-B V-Spec Original, Magnesium cooling head, 21H Carb 320.5g/11.3oz, Part#13893
OS Speed 21VZ-B V-Spec AL Same as original, Aluminum cooling head, 361.8g/12.46oz, Part#13894
OS Speed 21VZ-B SpecII Same as original, Drilled Aluminum cooling head, 21J Carb 349g/12.32oz, Part#13811
Protek 321B Samurai V2 Same as Speed, Drilled Aluminum cooling head, 355g/12.52oz, Part#PTK-2500
Ninja JX21 B01 5 port version of speed, OS 28XZ Case, no slugs in crank, Aluminum cooling head, 361.8g/12.46oz, Part#JX21B01
Ninja JX21 B01A Same as original JX, Drilled Aluminum cooling head, 374g/13.19oz, Part#JX21B01A
osspeed21vzbspecii.1785718870.txt.gz · Last modified: by nitroadmin