1975 was the last year for the Oldsmobile Delta 88 Royale convertible... and the last Olds ragtop, period, until the 1990 Cutlass Supreme.
Like the 1976 Cadillac Eldorado convertible, Oldsmobile really leaned into the future collectible hype, and they sold just shy of 7,200 units, including this beaut of a Horizon Blue example.
For the Delta 88 Royale, which was more upscale than the base Delta 88, the standard engine was the 350 Oldsmobile Rocket V-8 with a four-barrel Rochester carburetor. Optionally, the buyer could spring for the 455 Rocket four-barrel.
1975 was the first year for catalytic converters at Oldsmobile. This required the use of unleaded gas and saw greatly lowered compression ratios, and also meant dual exhausts went away (the exhaust system in the photo is therefore an aftermarket setup.) All this dropped output to 170 SAE net horsepower for the 350 and only 190 ponies for the big 455. A three-speed Turbo Hydra-matic was the only transmission on offer.
Among the available options was GM's then-new air cushion restraint system, but it couldn't be had on the convertible.
This one was photographed using a Canon EOS RP and an RF 24-105mm f/4-7.1 IS zoom lens in September of 2026.

