Stage 2 - These pumps from Stewart Components are assembled with exclusive Stewart Components 356-T6 heat-treated aluminum casting. These pumps include several significant performance modifications, compared to Stage 1 pumps, for maximum performance. Recommended for stock, OEM, or mild to moderate racing applications. All Stage 2 pumps feature: Exclusive Stewart 356-T6 heat treated aluminum casting Extra rigid cam stop with 3/8" adjustment screw (small block Chevrolet short castings) Extra material adjacent to block mounting bolts to allow drilling and taping of up to 1/2" NPT holes for installing external coolant lines to the center of the engine (small block and big block Chevrolet short castings) Precision ground fan hub for perfect pulley alignment.Equal flow to left and right cylinder heads. Precision impeller installed to exacting tolerance. Zinc plated rear cover bolt Higher flow and pressure for better cooling A full one-year warranty. Models with 3/4" ball/roller bearings offer five times the strength of standard bearings. Stock external dimensions and hose location Special water/antifreeze compatible seal assemblyPit Stop USA offers Stewart Stage 2 Aluminum Water Pump - Chevrolet BB - Short 21204 at low everyday prices. Be sure to check out all of our products from Stewart Components including Stewart Components Big Block Chevy Water Pumps.