hp 454 used in the 1970 Chevrolet Corvette and full-sized sedans. Chevrolet listed both gross and SAE net horsepower figures in 1971 with the impending change to SAE net ratings in 1972. The ratings compared as follows: The SS 454 package would be discontinued after this year following the production of 1,919 units, but the 454 CID V8 engine would remain optional in Monte Carlos through 1975. The reason given for discontinuing the SS was that the Monte Carlo was marketed as a luxury vehicle instead of a muscle car. The SS nameplate would be resurrected 12 years later. Yet, at the same time that the Monte Carlo SS was judged a failure in the marketplace and discontinued, the models' reputation as a performance car on the race track was gaining strength because Ford and Chrysler were ending their factory-backed racing support due to declining muscle car sales and the need to divert dollars to meet federal safety and emission regulations (General Motors' official policy had prohibited factory racing efforts since 1963). As factory support ended at Ford and Chrysler, the stock-car racing mantle switched to independent teams and sponsors, who overwhelmingly chose Chevrolets over Ford and Chrysler products due to Chevy's much greater availability and affordability of over-the-counter racing parts through the Chevy dealer network. The Monte Carlo was considered the best-suited Chevrolet model for stock car racing by most NASCAR teams due to its wheelbase (only one inch above NASCAR's minimum requirements at that time, the Chevelle 2-doors had a shorter 112-inch wheelbase) and long-hood design which placed the engine further back in the chassis than most other vehicles for better weight distribution. Thus the Monte Carlo became Chevy's standard-bearer for NASCAR from 1971 until 1989. Production of the 1971 Monte Carlo got off to a slow start due to a 67-day corporate-wide walkout (labor strike) that coincided with the introduction of the 1971 models in September 1970. This left dealerships with only a small shipment of 1971 models (built before the strike) in stock until the strike was settled in mid-November 1970, and then slow-going in reaching normal production levels until around January 1, 1971. Model-year production ended at 128,600 including the 1,919 SS models. A total of 12 1971 Monte Carlo's were shipped to Australia in 1971 and converted to RH drive, 4 of these were SS models from the 1,919 produced. 1972 A Cadillac-like egg-crate