HKS Step 1 capacity upgrade kit for longitudinal Nissan SR20DET engines. The 86.5 mm pistons and longer-stroke crankshaft increase displacement to 2,139 cc.
FITMENT Nissan 180SX (RPS13) January 1991–December 1998 — SR20DET. Nissan Silvia (PS13) January 1991–October 1993 — SR20DET. Nissan Silvia (S14) October 1993–December 1998 — SR20DET. Nissan Silvia (S15) January 1999–August 2002 — SR20DET. Not compatible with Nissan Pulsar / Sunny GTI-R (RNN14). Confirm the engine and block specification before ordering.
SPECIFICATIONS Part number: 21004-AN015 Stage: Step 1 Engine: SR20DET Finished bore: 86.5 mm Crankshaft stroke: 91.0 mm Displacement: 2,139 cc Piston pin diameter: 22 mm Forged pistons, H-beam connecting rods and forged full-counterweight crankshaft Boring and honing: required Full-flow modification: not required by HKS
PURCHASED PARTS PACKAGE Forged piston kit, H-beam connecting rods and forged crankshaft. This is an internal-component kit, not an assembled engine.
INSTALLATION AND USE Have an engine builder check machining, bearing clearances, compression ratio, gaskets and supporting engine management for the complete build. Step 1 uses 86.5 mm pistons; the 87.0 mm Step 2 kit is a different specification. Do not assume the Step 2 piston surface treatment applies to Step 1.
