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454

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Chevrolet's famous "big-block" 454 V8 was introduced in 1970, and replaced the 427 as the top-dog engine option. It's not often that an engine's debut year turns out to be its zenith year, but that certainly was the case with the 454. Besides being an optional workhorse engine for the pedestrian full-size Impala and Caprice, it also powered the Corvette and Chevelle SS in 390 hp LS5 and 450-460 hp LS6 guises, both which were vastly underrated (a common practice back then to avoid undue attention from insurance companies). A mint-condition numbers-matching 454 LS6 Chevelle or Corvette can now command a selling price well into the five digits, and its value is likely to continue increasing.

Since GM lowered compression ratios in 1971, the 454s horsepower ratings dipped a little but they were still substantial. The 1971 LS6 was now rated at 425 hp (the LS5 was 365 hp), and the revered LS6 was gone altogether by 1972. The LS5 remained and was now rated at 270 (due to the new gross vs. net hp ratings). The last "LS"-series 454 was the 1973 LS4, which took a last gasp at 275 hp, and found its way into a few Corvettes and Chevelle Lagunas. By 1974, the 454 was now pretty much the same across the board - the 454 in the Corvette was now the same 454 workhorse motor you got in your grandfather's Caprice. It's power was still very respectable, but its emphasis was now on its torque and pulling abilities instead of raw fire-breathing horsepower. The Corvette last used the 454 in 1975, and the 1976 Caprice/Impala was the last GM passenger car to use this engine.

The 454 now served duty as GM's truck line's top workhorse engine, and found its way under many C/K20 and C/K30 pickups, Suburbans and various GM-based motorhomes, although GM did offer this engine briefly in the 1/2 ton model in 1976-1978. In 1990, GM tried to revive the 454's previous performance image by offering a limited-edition 454 SS C1500 pickup model, although it was rated at only 230 hp, fairly paltry in comparison to the ground-pounders of the early '70s. It got a power boost to 255 in 1991, but the truck wasn't popular and was discontinued after 1993.

In 1996, the 454 got a full makeover and was now known as the "Vortec 7400" and got a power boost to 290. It continued in this present form until the end of 2000, where it was superceded by an all-new "Vortec 8100" (496 cid), which still continues today. The Chevy 454 to date is the longest-lasting big-block, lasting 31 model years - far outlasting its Chrysler 440 and Ford 460 big-block competition.