Based on a unit-body Chassis of 112 inch wheelbase shared with other GM compacts, the Tempest broke with engineering traditions with a four-cylinder engine, curved, torsion bare driveshaft and independent rear suspension differential transmission combination know as trans-axle. Vibration , the past enemy of four cylinder engines, was kept to a minimum by the extra-sturdy block and crankcase of the of the big four cylinder, and was isolated from the body by widely rubber mountings, The new engine developed 110 horsepower with the Manual transmission, 130 with the automatic.
As a result of new bodies for 61 Cadillac had easier entrance and comfort. Wheelbase was shortened 1/2 inch to 129.5 while over-all length got shortened by three inches to 222 inches. Tops of door openings got raised, sills narrowed and the “dogleg” corner of the windshield eliminated. Rear doors were six inches wider and swing open seven inches further than previous models. Headroom in the four window sedan and the coup was increased by two inches. Due to changes in the position of the engine and transmission the tunnels were lowered in both front and rear compartments. The Sixty Special four-door hardtop sedan became the top of the line in 1961 because the Eldorado Brougham was dropped. Seating comfort was improved by lowering the front floor, increasing “Chair Height”.
The 61 Thunderbird was virtually a new car except for it’s 390-cubic-inch V-8 engine and the classic Cruse-O-Matic automatic transmission. Overall dimensions were 205 inches long, 52 1/2 inch high and a 113 inch wheel base. This was the appearance of the “torpedo” and a roomier interior even tho it was still described as a four passenger car.
In 61 the Lark go a new hood with a flatter cowl than previous years,
which allowed a larger windshield and a lower over-all height, other changed included dual headlights, restyled side trim, different rear quarter roof, a more attractive back glass and a new rear deck lid.