1966 Chevrolet Chevelle SS 396: The Supercar Gets Its Own Series, and a Third Engine the Brochure Left Out

When Motor Trend’s John Ethridge wrote up the new Chevelle SS 396 for the February 1966 issue, he said there were “only two engines available for the SS”: the standard 325-horsepower 396 and his test car’s 360-horsepower version, with its higher-lift, longer-duration camshaft. Chevrolet’s own 1966 brochure agreed. It listed a 325-hp Turbo-Jet 396 as standard and a 360-hp Turbo-Jet 396 as “available only with SS 396.” By the end of the model year, though, Chevrolet’s option report had counted 3,099 SS 396s built with a third engine, the 375-horsepower L78. The first full year of the SS 396 opened with two engines on paper and closed with three on the assembly line.^1,2

The car Ethridge tested was a different animal from the one Chevrolet had sold a year earlier. In 1965 the 396 reached the Chevelle through RPO Z16, a $1,501.05 option recorded on just 201 cars with a 375-horsepower engine. Ethridge called that car the “special, limited-production 1965¾ Malibu SS 396.” For 1966 Chevrolet made the SS 396 a series of its own, separate from the 300, 300 Deluxe and Malibu, with Fisher Body style numbers 13817 for the sport coupe and 13867 for the convertible. Every one was a V8, and there was no SS 396 El Camino. The Super Sport had stopped being an exotic special and become a model.^3,1,2

Ordinary parts carried much of the transformation. Motor Trend reported that the 1966 car used standard Chevelle brakes and suspension throughout, except for springs about 30 percent stiffer, heavy-duty shock valving and a stiffer front stabilizer bar, with no rear bar. The rear axle got a sturdier carrier with an 8.875-inch ring gear, and the frame carried a pair of reinforcement members. The brochure promised simulated twin hood intakes, red-stripe tires and a fully synchronized floor-shifted three-speed. ChevelleStuff adds that the standard car had a front bench and no gauges beyond the speedometer, clock and fuel gauge. Motor Trend listed the sport coupe at $2,776.^1,2

Buyers took to it at a rate the Z16 never approached. The reference tabulation, which it says agrees with Chevrolet’s Accumulative Production Report of August 2, 1966, lists 66,843 SS 396 sport coupes and 5,429 convertibles, 72,272 SS 396s in all, and not one six-cylinder. Coupes outnumbered convertibles by about twelve to one. The SS 396 sport coupe count alone was about half the 130,540 V8 Malibu two-door coupes built alongside it. Across the whole 447,364-car Chevelle line, El Camino included, about one car in six was an SS 396. The big-block intermediate had become a volume product in a single season.²

Within that total, Chevrolet’s option report shows how far buyers stepped up. The 360-horsepower L34, a $105.35 option, went into 24,811 cars, about a third of the 72,272 SS 396s. The L78, listed at $237.00, went into 3,099, a little over 4 percent. The report also carries an L35 line of 1,865, but that is an option-report quantity and not a count of base engines, because the 325-horsepower engine came with the car. What remains unknown is just as telling. The records here do not say when the L78 entered the order book, only that it was there by the time the year’s counts closed.²

The rest of the order form describes a car still finding its footing. Across the Chevelle line, El Camino included, 73,022 buyers chose the M20 wide-range four-speed and 5,012 the M21 close-ratio unit, while only 12 are recorded with the M22. Powerglide, the two-speed automatic, went into 292,437 Chevelles. No front disc brakes were offered; Motor Trend’s price list shows them as not available, and 7,837 buyers took sintered-metallic linings instead. The $79 special instrumentation package, with the tachometer, went into 32,436 cars. Positraction went into 67,905.^2,1

Ethridge’s test car carried the L34, a four-speed and a 3.31:1 axle, and came to $3,888.10 as tested. It ran 0-60 mph in 7.9 seconds and the standing quarter mile in 15.5 seconds at 89 mph, at a curb weight of 3,800 pounds. His companion Malibu, a Powerglide 283 chosen as the average buyer’s car, needed 19.5 seconds. The SS returned between 10.4 and 14 mpg on super-premium fuel. He liked it on a long highway trip, calling it neither boring nor punishing. He did find that a steering-wheel spoke hid the optional tachometer. The magazine also drove it around the street circuit of the Juárez, Mexico, Grand Prix.¹

Car and Driver’s March 1966 comparison set the SS 396 against a GTO, Fairlane GT/A, Comet Cyclone GT, Buick Skylark Gran Sport and Oldsmobile 4-4-2. It ran them at the Westhampton drag strip and on the Bridgehampton road circuit, where Masten Gregory drove the timed laps. The magazine said openly that some rivals arrived prepared. Pontiac announced a Royal Bobcat conversion, Holman and Moody went over the Fairlane, and Bud Moore’s shop set up the Comet. The Chevelle was no hero at Bridgehampton at first. It overheated on its opening runs, and Gregory disliked the long throw from second to third, which the Hurst crew shortened.⁴

Car and Driver’s verdict on reliability was the most revealing line in the test. “Ironically,” the magazine wrote, it was the three most stock machines, the Chevelle, the Buick and the 4-4-2, that gave the least trouble. The Chevelle still did not escape without damage and was listed among the test’s casualties, and Gregory again found the tachometer blocked by a steering-wheel spoke. The magazine noted that not one of the six cars arrived with disc brakes. As in Motor Trend’s test, the numbers belong to the individual prepared cars. What the comparison documents is a showroom-grade SS 396 finishing the event among the dependable cars.⁴

The Chevelle SS 396 kept its format for 1967, still a separate series in sport coupe and convertible form, but the details shifted. The L34 option came back rated at 350 horsepower instead of 360. Front disc brakes appeared on the option list and went into 5,153 Chevelles. The L78 slipped further out of sight: the reference calls it a late, unannounced option and counts only 612. SS 396 production eased to 59,685 sport coupes and 3,321 convertibles. The 1966 season remained the one in which the big-block Chevelle first sold in real numbers, well beyond the 201 Z16 cars that came before it.^5,3