Chevrolet Chevelle SS 454

When fantasy collides head-on with reality something’s got to give, and, unfortunately, reality usually wins out. So it was with the famous Chevrolet Chevelle SS 454. In this case, the fantasy was having a National Hot Rod Association Pro Stocker virtually straight out of the box from your local Chevy dealer. The reality was  consumer concern for fuel economy, tightening exhaust emission controls, and the costliness of small production runs. In the end, reality overwhelmed the SS 454, but for several shining moments the car showed how hot a factory-built hot rod could be.

We have outlined the history of the Chevrolet Chevelle in a separate article (see Chevrolet Chevelle SS 396), but for the sake of   historical accuracy and clarity, let’s run through it quickly here. The “mid-sized” Chevelle sprang full-grown from GM’s A-body platform that also supported the  Pontiac Tempest, Oldsmobile F-85, and Buick Special. It hit the market at the start of the 1964 model year.

Standard American cars

The original F-85, Tempest, and Special all had their share of idiosyncratic  characteristics, but in their second incarnation, all the weirdness was engineered out of them. Instead, they became “ordinary American cars,” so generic in construction and engineering  that each could well have worn a blue stripe. With this as its underpinning, there was nothing leading-edge about the Chevelle either, but while some might have held that against the car, to others it was a blessing. If you knew anything about automobiles, you could work on a Chevelle.

Inserted between the Chevy II and the full-size Chevrolet line, the Chevelle rode on a 115-inch wheelbase. Front engine, rear drive of course, the Chevelle’s suspension was also pretty uncomplicated–an independent A-arm front and a live axle in the rear. In its standard  form, the car had few performance aspirations. Instead, it was a super-reliable family car, capable of  transporting six passengers on its two bench seats and a decent amount of luggage.

Its original “Super Sport” model was more style than substance. The 220-horsepower 283 V-8 engine was part of a package that offered front bucket seats, tachometer,  sintered-metallic brake linings (for the mundane drum brakes), available Positraction limited-slip differential, and a four-speed manual transmission. As the model year progressed, the Chevelle engine options expanded to include two 327 cubic inch V-8’s with horsepower ratings of 250 and 300. But the car was not a  threat to a big-block-equipped Pontiac GTO.

Initial challenger to the GTO

With the success of the GTO, General Motors started  to lighten up its corporate procedure that had restricted the use of so-called big-block engines in intermediate-sized cars. The fear was that too much horsepower might result in rampant mayhem–plus huge insurance premiums. Chevy’s first crack at the GTO was the 1965 Z16 Chevelle, a low-volume nearly secret option that included the 396-cubic-inch V-8 engine providing  some 375 (gross) horsepower. That car led directly to the Super Sports 396 of 1966, a vehicle that also highlighted  a sleeker exterior.

The lowest level SS 396  provided  a 325-horsepower version of the 396 cubic inch V-8, and the up-level “street” version with the L34 hydraulic-lifter-equipped engine supplied  360 horsepower. And if you wanted to imagine  you were a race driver, you could pony up the extra bucks for the 375-horsepower solid-lifter version, though few went to that extreme. With a sub-15-second quarter mile time from the L34,  there was really no reason to opt for the high-maintenance solid-lifter models.

The SS 396 proved to be a huge  hit in the marketplace. It was a practical family car (although one that offered dismal fuel economy) that could also win most stoplight derbies. Its cornering ability was never on par with its straight-line ability, but if you like the feel of torque and power  (and who doesn’t?) the SS 396 had it in spades.

A solid victory gets better handling

By the time the 1968 model year rolled around, the SS 396 was solidly successful, so GM was willing to spend  yet more money in the sub-model.  The fact is, GM engineers decided to build two different chassis for the ’68 Chevelle. The mundane 4-door sedans rode on a 116-inch wheelbase, while the coupes,  as well as  the SS 396, got a tauter 112-inch wheelbase. This didn’t turn the Chevelle into a Ferrari, but the shorter wheelbase, along with other tweaks like the  inclined front control arms and the addition of sway bars   helped upgrade the previous model’s handling.

By 1970, the Chevelle was  armed  with an even bigger big-block. The same basic block was stroked and  bored  to achieve a displacement of 454 cubic inches, and the model designation shifted to SS 454 for the sake of symmetry. Each cylinder bore in the monster motor was nearly the same as that  of a quart-sized tomato juice can.  Huge and fuel-thirsty but who cared in those days?

While the 396 cubic inch engine stayed  in the lineup, two versions of the 454 trumped that solid performer. Semi-rational human beings opted for the LS-5  models  of the 454. With a potent 10.25:1 compression ratio and  hydraulic lifters, this version was said to be good for 365 (gross) horsepower. Arguably, this SS 454 versioin was the most streetable all-around performer of the SS series.

Pure racing enthusiasts  took things one step further. They ordered the LS-6 454 version featuring solid valve lifters and a  surprising  11:1 compression ratio. General Motors claimed the engine developed 450 gross horsepower. Straight-line times for the LS-6 SS 454 were truly outstanding. Different  magazines claimed zero-to-60 miles per hour clockings as low as the mid-five second range. Road testers saw quarter mile times of under 14 seconds, this from a car that could be bought off the showroom floor. Fantasy shockingly come to life!

Fantasy hits fuel reality

But by the year  1970, fantasy was plummeting headlong into reality. The SS 454’s days were coming to an end.  First, for the ’71 model year,  General Motors decided that all of its products should be tuned to run on unleaded gas. The lower octane of the unleaded fuel led to the emasculation of the two 454 engines. The LS-5 was de-tuned to a 8.5:1 compression ratio, and, though GM still claimed 365 horsepower for the beast, it is doubtful the engine really offered that much. The LS-6 version plummeted  to a 9:1 compression ratio and 425 horsepower, and further it seems unlikely that any 1971 LS-6-equipped cars were actually delivered to non-racing customers. The car still looked good, and with the LS-5 street engine it performed well, but the end was quickly drawing near.

By 1972, with reality closing in, the SS 454 was on its final legs. The LS-5 engine was still available, but GM decided to switch to SAE net horsepower ratings in ’72 versus the gross horsepower ratings used formerly, so the emission-choked car looked even more anemic with its 270 claimed horsepower. In reality,  the engine was not much different from the prior year, but the switch reflected the insurance companies’ new sway with automakers. The ’73 SS 454, with an all-new body style, boasted just 245 horsepower, and the following year the SS option package disappeared  from the scene as the first oil crisis changed everything about the auto industry in a matter of a few dreadful months.

Reality had triumphed one more.

—© Studio One Networks—

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