1912 Pierce-Arrow Model 66 (more pics below π)
Commanding proportions defined Pierce-Arrow’s flagship model, with coachwork that sat passengers high above the road in what was widely considered one of the largest and most impressive automobiles of the Brass Era.
The massive T-head inline-six engine drove development of the entire chassis, requiring substantial frame construction and heavy-duty components to handle the forces involved.β
Introduced in 1910 with 714 cubic inches of displacement, the powerplant grew to about 825 cubic inches by 1912. Despite retaining the Model 66 designation (originally indicating 66 rated horsepower), actual output had climbed well into triple digits by that point, with later versions quoted at roughly 125 to 140 brake horsepower depending on tune and year.
The engine’s long stroke delivered substantial torque for moving the hefty chassis and luxurious bodywork typical of Pierce-Arrow construction. Guinness World Records and multiple marque authorities have long recognized the roughly 13.5-liter Model 66 engine as the largest displacement unit ever installed in a production automobile.β
Between 1910 and 1918, approximately 1,250 examples of the Model 66 were built. Most survivors remain in private collections, with only a small handful recorded today, and they rarely appear for public sale, making these automobiles among the most sought-after machines from the brass car period.
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