The raw power to exploit a split-second opportunity is there, tempered by the ability to fine-tune and finesse throttle control to the needs of different tracks and situations. And to help keep the 21VZ-B V-Spec-T (P) at the peak of its power, O.S. has given it a billet aluminum piston, hardened ABC sleeve for added wear resistance and a new crankshaft design that's simultaneously slimmer and stronger than any O.S. crankshaft ever made. The 21VZ-B V-Spec-T (P) — designed for first-place finishes over the long haul — from O.S.
* More power and durability. The brass sleeve is chrome-plated for performance and hardened to withstand the wear that racing action can produce. CAD-refined and CNC-machined ports smooth airflow and boost power.
* Track-tune in seconds! Increase control on low-traction tracks by inserting the 8 mm (red) or 9 mm (blue) carb restrictor. Takes only a second, but pays off, lap after lap.
Displacement: .21 cu in (3.5 cc)
Bore: 0.653 in (16.6 mm)
Stroke: 0.629 in (16.0 mm)
Practical rpm: 3,000-40,000
Output: 2.5 hp @ 33,000 rpm
Weight (w/o muffler): 12.7 oz (360 g)