(first posted 10/12/2012) All bow(tie) before the greatest American engine of the postwar era! Yes, I suppose that’s easy to say, considering what an icon it has become. And no, it wasn’t the first to proclaim an advertised one-horsepower-per-cubic inch (for what it’s worth, that title was claimed by the 1956 Chrysler 300B’s optional dual-quad Hemi engine.) Nevertheless, Chevy’s compact, thin-wall V8 became the de facto template for almost every subsequent American V8; what’s more, when fitted with 1957’s Ram-Jet fuel injection, it was by far the most advanced engine around, and it made the 1957 Corvette the quickest production car in the world. Indeed, Chevrolet’s abandonment of port FI until the mid-’80s is among its Deadly Sins, but that’s another story.
The Rochester mechanical continuous-port injection system actually wasn’t designed by Rochester. It was the brainchild of a team of GM engineers who undoubtedly received encouragement from Zora Arkus-Duntov and Ed Cole. The prospect of exploiting the benefits of fuel injection in increasing both performance and economy must have seemed tantalizing to them–and the result of their work certainly achieved those goals.
If you’d like to know just how it actually works, Chevrolet published a well-illustrated training brochure that explains it very thoroughly, but in a way that is quite accessible to anyone with a basic understanding of engines and fuel delivery systems. The whole brochure is accessible here (oldcarbrochures.com)
Certainly, the ability to achieve 20 mpg in easy highway driving was appreciated by those who’d paid the substantial $550 premium for fenders displaying the iconic fuel injection badge. Another benefit of the fuel injection was an overwhelming power band, with no flat spots, that simply was unparalleled anywhere else in the world–except, perhaps, in the direct-injected engine of the Mercedes 300SL at double or triple the price. Still, the fuel-injected Corvette was the quickest production car in the world, handily out-accelerating the 300SL.
The 283 fuelie could rev cleanly to 7,000 rpm, yet idle (reasonably) happily at some 900 rpm, which in 1957 was simply unheard of. And the performance numbers it produced in a 1957 Corvette are still impressive, unless we’ve become totally jaded by 5.7-second 0-60 times (300SL: 7.4 – 7.7 seconds). In a period R&T test, the ‘Vette peeled off a 14.3 second 1/4 mile time (300SL: 15.5-16.0 seconds). Let’s not forget that was over a half-century ago, and such numbers would be hard to beat by any vintage Corvette, even during the golden big-block era, never mind the long, dark ’70s and early ’80s.
Despite an official ban on racing activities, the ’57 fuel-injected Corvette quickly racked up an enviable record on the race track, with back-door support from Chevrolet.
The Rochester injection system could be a bit finicky, and it did have a number of well-known weaknesses, most of which were reduced or eliminated over its nine-year production run. In the hands of those unwilling to learn its secrets, the beautiful cast and polished aluminum crown was all too often tossed aside for carburetors, typically the dual four-barrel setup used on the 270 (gross) hp production version. And how many would regret that decision in later years, when a genuine fuel-injected Chevy or Corvette would become much more valuable.
The jalopyjournal‘s comment thread on the Chevy fuel injection includes a number of fascinating anecdotes and experiences from former (and current) Ram-Air owners (and is also a source for a couple of the images here). It paints the same picture as so many a new technology: Many mechanics (and owners) were stumped by the Rochester’s quirks and foibles, and encouraged tossing it aside for carbs. But those that mastered it were rewarded by superb driveability, economy and, of course, performance; as long as one knew what parts to keep on hand, it could even be quite reliable.
The same story played itself out with the early Bosch fuel-injected VW Type 3s: That system often was converted to carbs, but those that mastered it were also well rewarded.
The modest number of ’57 Chevrolets actually equipped with fuel injection dwindled in 1958, when the new 348 cu in W-block engine represented the equation for the next few decades: Ever-bigger displacement, and topped by a carburetor(s).
But this ad from 1959 the 290 hp 283 backed by the four-speed manual and heavy duty suspension were still being promoted as a “sports car…for five!”
The Corvette kept the FI torch blazing brightly through 1965, right up to the brilliant 375 (gross) hp, 327 cu in (5.4-liter) version, perhaps the ultimate Chevy small block. I’ll never forget the day one pulled in to fill up with 260 at the Sunoco station where I worked Saturdays back in my high school days. When I opened the hood to check the oil, I was almost overcome by the combination of all that fine-looking alloy and the crackling heat it was throwing off on a hot day. Now that was a moment of veneration.
But the availability of Corvette big-block engines that began in 1965.5 sounded the death knell for the fuelie 327, even though its lighter weight (and better handling) would have made it my choice had someone offered me a C2.
Clearly, the Rochester FI was too expensive for its time, with a cost-benefit ratio that hardly was attractive to anyone but racers and the cognoscenti. But killing it wasn’t a forward-looking decision: This (somewhat tacky) 1957 promotional video touting the new Ram Air’s benefits mentions its ability to reduce smog. In reality, that was an issue GM (and the rest of Detroit) ducked as long as possible, but it was ever-tightening government standards that finally brought back proper fuel injection, a process that took a lot more time than it should have.