The 1973 model year was the cliff's edge for the original performance car era in Detroit. Engines had been lowered in compression to meet new emissions standards and to improve fuel economy, and were now advertised by SAE net rather than gross horsepower ratings, as though to emphasize the haircut in output.
All cars were required to sport grotesque new front bumpers that would absorb a 5MPH impact without structural damage (they'd be joined by matching rear protuberances for the following year.) The premier performance models from Ford and Pontiac were about to enter the dark ages: The 1974 Pontiac GTO would be a Nova and the '74 Mustang would morph into a Pinto.
At Oldsmobile, the only convertible left in the lineup for 1973 was the Delta 88 Royale, like the silver example in the photo above.
The '73 Delta 88 ragtop came with a base 160 horsepower 2-barrel version of the Olds 350 Rocket V-8. For an upgrade, the buyer could opt for a 4-bbl 455 cube Rocket, in either 225bhp or 250bhp format, with the latter sporting a dual exhaust setup.
The car in the picture has had the top replaced and has been repainted in the original Silver Taupe, with its lines slightly cleaned up by removing the chrome faux louvers that normally appeared on the front fenders.
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