For a GM product of this vintage north of the Ohio river that appears for all the world to be a daily driver, the fact that this thing's not a rusted out hulk is a wonder.
If I'm reading the tea leaves of the grille inserts correctly, this Light Blue Metallic Oldsmobile Delta 88 Royale Brougham coupe is a 1980 model.
The eighth generation of the Oldsmobile 88 ran from the 1977 through the 1985 model years. Sharing the same platform as the Buick LeSabre, Chevy Caprice, and Pontiac Bonneville, it represented the first round of downsizing for General Motors full-size cars, losing eight inches of wheelbase relative to their '71-'76 predecessors.
The 1980 model year represented the first styling refresh for this generation, and was one of the last model years to feature brand-specific engines, as GM was gradually homogenizing their powertrain lineup. (The first steps in this direction caused a bit of a stink in 1977.)
For the 1980 model year, the base motor was a 110 horsepower Buick 3.8L V6. The next step up was the 260 cubic inch (4.3L) version of the Olds Rocket V8, with 307 cid and 350 cid versions also available. These were rated at 120, 150, and 160 horsepower, respectively.
Also available as an option was the disastrous Olds 350 diesel V8, which put out 105 SAE net horsepower when you could get it to run at all.
Alas, the 185-horsepower 403 cubic inch 4-barrel Rocket V-8 was discontinued after the '79 model year. It had been a sluggish seller due to fuel economy concerns.
You could get the 1980 Delta 88 models in plain, Royale, and Royale Brougham flavors, with each one having a more deluxe list of features as standard. The Royale Brougham was crowding basic Cadillac models when it came to included features.
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