W/P Pulley Gilmer 28T

The W/P Pulley Gilmer 28T by Peterson Fluid is a precision water pump pulley engineered for high-performance engine builds and serpentine belt drive systems. This compact, lightweight component is essential for mechanics and enthusiasts upgrading cooling systems on small-block engines where belt drive ratios demand precise pulley geometry. The 28-tooth Gilmer profile ensures reliable engagement with HTD-profile serpentine belts, making it ideal for custom engine packages, LS swaps, and performance cooling applications where OEM pulleys fall short.

Machined from durable aluminum, the W/P Pulley Gilmer 28T features the Gilmer tooth profile—a synchronous design that eliminates belt slip and ensures consistent pulley velocity ratios across engine rpm ranges. The 28-tooth configuration delivers optimal belt tension and wrap angle for water pump drives without over-speeding the cooling system, a critical factor in forced-induction and high-rpm applications. Peterson Fluid pulleys are manufactured to tight tolerances, ensuring concentricity with the water pump shaft and reducing vibration that can degrade belt life and bearing longevity on modified engines.

This pulley suits engine builders transitioning from traditional V-belt systems to modern serpentine drives or calibrating belt drive ratios on carbureted and fuel-injected street engines. Weighing just 0.63 lbs, the compact 28-tooth design integrates seamlessly into tight engine bays and works with Peterson Fluid's complete line of crankshaft and accessory drive pulleys. Installation requires standard bearing removal tools and pulley alignment fixtures; compatibility depends on water pump shaft diameter and serpentine belt width (typically 3/8-inch or 1/2-inch HTD). Verify shaft fitment and belt routing before ordering to ensure proper fit on your specific engine platform.