Beginning with the 1964 model year, the Buick Skylark, along with the lower-priced Special from which it was derived, would move to a new intermediate-size chassis that was shared with the Oldsmobile F-85, Pontiac Tempest, and the new Chevrolet Chevelle. The new chassis had a wheelbase of 115 in (2,921 mm) and the Buick Special and Skylark had a length of 203.5 in (5,169 mm). The 215 cubic-inch-displacement aluminum block V8 engine was discontinued, and the associated tooling eventually was sold to the British manufacturer, Rover. That company would produce the engine in several versions for use in its sedans and Land Rover sport utility vehicles and trucks.
The standard Skylark engine was now a 225 cubic-inch all cast iron block V6 with a Rochester 1-barrel carburetor that generated 155 hp (116 kW) at 4400 rpm. This engine was introduced in 1964, very similar to the earlier V6 beginning with the 1962 model year which had a smaller displacement of 196 cubic-inch. This engine was basically a Buick V8 300 CID engine with two cylinders sawed-off. The optional engine was a 300 cubic inch cast iron block and aluminum heads V8 with a Rochester 2-barrel carburetor that generated 210 hp (160 kW) at 4600 rpm. An optional V8 version of the 300 CID engine was offered with a 11:1 compression and a 4-barrel carburetor generating 250 hp (190 kW). A long-throw, 4-speed Hurst shifter was available. For the 1965 model cast iron blocks and heads were used for all engines.
In addition to the two-door convertible and hardtop coupe body-styles, a Skylark four-door sedan became available for the first time. Skylarks, however, would continue to have higher levels of exterior and interior trim compared to the Special and Special Deluxe from which they were derived. All-vinyl bucket seats would be standard on the convertible and optional on the hardtop coupe. The sedan would come with cloth-and-vinyl seats standard, and an all-vinyl interior would be optional. The Sylark Coupe had a lower profile, sitting lower to the road than the Buick Special models.
The Skylark in 1964-1965 were available in a pillar-less coupe (Hard Top) two-door sedan version, as the Specials and Special Deluxes only came in pillared coupe versions. Beginning with the 1964 model year, a two-door sedan (pillared coupe) was added to the Skylark lineup. Inspired in no small part by the sales success of the 1964 Pontiac Tempest, LeMans, GTO, the Gran Sport option became available in mid 1965 for the three two-door Skylark models. The Gran Sport option featured Buick’s 401 cubic-inch-displacement V8 engine using a Carter 4-barrel carburetor that produced 325 hp (242 kW) at 4400 rpm (it was listed as 400 cubic inches in sales literature, supposedly to escape a General Motors mandate that engines larger than 400 cubic inches should not be used in intermediate-sized cars). Other Gran Sport features were unique Gran Sport badging, a heavy-duty radiator, and dual exhaust.
Source: Wikipedia, 2012