GP-1 20w50 SemiSynthetic Case 4 x 1 Gallon

The GP-1 20w50 SemiSynthetic Case 4 x 1 Gallon from Driven Racing Oil is engineered for high-performance engines that demand robust film strength and thermal stability under extreme load. This semi-synthetic formulation strikes the balance serious mechanics and engine builders seek—delivering the protective benefits of synthetics without the premium cost of full synthetics. Whether you're running a naturally aspirated stroker, a turbo street engine, or a vintage hot rod with modern internals, this 20w50 viscosity grade provides the shear stability and anti-wear additives necessary for sustained power delivery and engine longevity.

Driven Racing Oil's semi-synthetic technology combines mineral base stocks with synthetic esters and advanced additive packages, creating an oil that flows reliably at cold startup while maintaining a protective 50-weight film at operating temperatures. The 20w50 grade is ideal for larger-displacement engines and modified power plants where ring blow-by and bearing clearances demand heavier viscosity protection—especially in flat-tappet or solid-lifter cam applications prone to accelerated wear. The proprietary zinc and phosphorus anti-wear package protects valve train components and cam lobes during the critical break-in phase and throughout the engine's service life, resisting oxidation and deposit formation even under continuous high-rpm operation.

This four-gallon case is the go-to choice for engine builders stocking their shop, restoration enthusiasts doing complete rebuilds, and track-focused drivers who change oil frequently between events. The 20w50 weight suits big-block Chevys, Ford FE and 427 engines, classic muscle car restomods, and any application where ambient temperatures remain moderate to warm. Compatibility is universal across conventional and semi-synthetic engine designs; simply confirm your owner's manual or builder's specification calls for SAE 50-weight protection, and this Driven Racing Oil case delivers the thermal control and anti-wear insurance every high-performance engine deserves.