1970 Oldsmobile 442 W-30
General Motors lifted its displacement restrictions for 1970, allowing Oldsmobile to install the 455 cubic inch (7.5-liter) V8 as standard equipment in the 442.
The W-30 performance package elevated this platform further through functional forced-air induction via a fiberglass hood with dual scoops, an aluminum intake manifold, a high-performance hydraulic camshaft, and a specially calibrated Rochester Quadrajet carburetor feeding large-port cylinder heads.
Factory rating stood at 370 horsepower at 5,200 rpm with 500 lb-ft of torque at 3,600 rpm from the 10.5:1 compression ratio engine, although independent tests and period sources often suggested the actual output was closer to 400 horsepower.
Production totaled approximately 3,100 W-30 examples for 1970 across all body styles, with distinctive red plastic inner fenders serving as a visual identifier of the package. The M21 close-ratio four-speed transmission with Hurst floor shifter was available, along with the Turbo Hydra-Matic 400 automatic, and either could be paired with the G88 3.91 Anti-Spin (Positraction) differential.
A very small number were further equipped with the rare W-27 aluminum rear axle housing and cover, which reduced unsprung weight by about 22 pounds compared to standard cast iron components while also helping rear axle cooling.
The 455 Rocket V8 with W-30 specification represented the most powerful engine configuration offered in an Oldsmobile intermediate-size car and is widely regarded as the peak of factory performance for the 442 line, arriving just before compression ratios and advertised outputs dropped to accommodate lower-octane fuel and changing emissions requirements for 1971 and later.
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