1961 CHEVROLET IMPALA BUBBLE TOP

1961 CHEVROLET IMPALA BUBBLE TOP                                                            NO 28

Called BUBBLE TOP because of the large back window

Canadian Car made at the Oshawa GM Plant

Engine: 348 cid                       Automatic transmission                         Original MSRP: $2,708.00

Power Brakes cost $43.00    Wheelbase: 119 in                                     Curb Weight: 3480 lbs

Impalas featured premium interior appointments over other Chevrolets. One design feature that was included on all of the 1961 Chevrolet Impala models was the use of a triple taillight assembly on each side of the back of the car. The Biscayne and Bel Air models only had two lights per side and the wagon only one. On the Impalas crossed-flag insignias were attached above the side moldings. This means that this is a “Sport Coupe” model.

“Over the years this model was available, I believe the 1961 model year is the most iconic of this design.” (TL)

The rugged, powerful 348 cu in engine and subsequent even stronger 409 cu in engines were favorite choices of drag and street racers during the `60’s and so there are few examples left. Hence, those survivors are a favorite collector’s item as being representative of those times.

Chevrolet Family of V8 Engines (1955 – 1965)

The post war period saw automobiles increasing in size and weight. Engines to power them had to keep up. GM developed a parallel series of V8 engine families that would evolve to fill the bill. They divided their new engines into small block and big block versions. As we have seen the “Small Block” V-8 engine was introduced in the 1955 Chevrolet Bel Air and Corvette models. For GM “Small Block” V8’s have come to mean everything below 400 cid displacement. The “Big Block” V-8’s came to mean those above 400 cid.

Originally designed for passenger cars and light trucks, the “first version of the `Big Block’ Chevrolet engine, known as the W-series, was introduced in 1958. The engine had an overhead valve design with offset valves and uniquely scalloped rocker covers, giving it a distinctive appearance. The W-series was produced from 1958 to 1965, and had three displacement options.

+ 348 cid (5.7 L) available from 1958 – 1961

+ 409 cid (6.702L) available from 1961 – 1965

+ 427 cid (6.9973 L) available from 1962-1963

“The W-series was made of cast iron. The engine had 4.84-inch bore centers, two-main bearing caps, a “side oiling” lubrication system (the main oil gallery located low on the driver’s side of the crankcase), with full-flow oil filter, and interchangeable cylinder heads. Heads used on the high performance 409 and 427 engines had larger ports and valves than those used on the 348… but were externally identical to the standard units. One minor difference between the 348 and 409/427 was the location of the engine oil dipstick. It was on the driver’s side on the former (348) and the passenger side on the later (409/427). No satisfactory explanation for this change was (ever) made.

“The 409 cid (6.7L) version was Chevrolet’ stop regular production engine from 1961 to 1966 with a choice of single or dual four-barrel carburetors. Bore and stoke were both up from the 348 to 4.312 in (109.5 mm) by 3.50 in. (88.9 mm). . . a 409 hp (305 kW) version of this engine was also available, developing 1 hp per cubic inch with a dual four-barrel aluminum intake manifold and two Carter AFB carburetors. It had a forged steel crankshaft. This version was immortalized in the Beach Boys song `409.’

“In the 1963 model year, output reached 425 hp (317 kW0 at 6200 rpm with the 2x4 setup, 11.25:1 compression and a solid lifter camshaft. The engine was available through mid-1965 when it was replaced by the 396 cid 375 hp (280 kW) Mark IV big-block engine.” (GM Engines, wikipedia)

So, the debate goes on: Did the Muscle Car Era begin with John DeLoren slapping that big engine 396 V8 in the intermediate Tempest body in 1964 or did the need for speed start earlier. Among the alternative cases that could be made would feature Chrysler’s Hemi powered letter series 300 in 1955 or the Big Block V8’s of Chevrolet introduced in 1958. But it really doesn’t matter does it because no matter what or when, it was a hell of a ride!