Once endangered, now on the rise.
Why I stopped the swap: Falling in love with the inline-6
Tuco, the clown villain (or “the ugly”) in “The Good, the Bad and the Ugly,” was right. There are two kinds of people in this world. And in the classic car world, there are those who leave classic cars stock and those who—woo hoo!—want to make them go faster, my friend.
In which category do you belong? I am, for better or worse, solidly among the latter. I can’t help myself. While I can concede that the automotive engineers from Detroit or Tokyo or wherever knew what they were doing (most of them anyway), I still feel compelled to second guess and improve upon their work. You see, the thought that design compromises were made in the interest of lowering cost and increasing sales volume is a constant source of upheaval for me.
“Come on,” says my internal voice as it pulls the strings that cause me to squirm, figure, and, ultimately, spend money on foolhardy projects. “Those guys were a bunch of bean counters. They didn’t really have your best interests at heart. You can unlock this car’s potential!”
While this prodding feeling may or may not reveal any actual truth, it’s there nonetheless, so I—like so many others like me—feel compelled to make “improvements” to the cars I buy. Therefore it stands to reason that when I bought a ’65 Chevy Malibu sedan last year, the idea that I’d swap the engine for something more powerful existed before I’d even clicked “Buy It Now” on the eBay listing. Rip out the inline-six and pop in a souped-up small block V-8; that’s the ticket.
When I retrieved the car from a quiet corner of rural Wisconsin (I’d gone with the shoot-first-ask-questions-later approach, buying it sight-unseen, flying there with a bag of basic tools, and driving it back to the East Coast)—I had already formulated a plan as to how I was going to turn the four-door sedan into the last word in ’60s sleeper muscle sedans. This Malibu was going to be a roaring V-8 monster worthy of a Beach Boys song.
But then I drove it. Its 230-cubic-inch inline-six engine—the original, as far as I could tell—was smooth and torquey. I liked the sound it made, so friendly and so unlike a V-8. It seemed natural in a car with bench seats, a column shifter, and four doors. Then I began to consider all the things I would have to change if I wanted to go the high-horsepower V-8 route. Manual, single-circuit drum brakes (front and rear) were a potential recipe for disaster. The steering was too slow. The tires too thin. The seatbelts were, well, non-existent. The car’s rear axle—General Motors’ mediocre corporate 10-bolt—was a little small for the manual transmission swap I had in mind, too.
On top of all that, I simply enjoyed floating along on my wheeled couch, one finger resting on the thin rim of the car’s huge steering wheel to keep it pointed in the right direction. All I needed was a trilby, a checked blazer, and a pack of Viceroys to complete the feeling that I’d somehow transformed into a midcentury bureaucrat who would never have thrown down the extra scratch for the V-8 option.
Once I had resolved to do a service to “inline-sixdom” and keep the skinny mill, my mind drifted naturally into the realm of potential mechanical improvements. After all, the Malibu was built at a time when high gearing and non-overdrive transmissions were the norm. I intended to take advantage of lower gearing and a modern overdrive transmission.
There were engine upgrades to be made, too. Rather than scrapping a smooth, pleasant engine like the 230, I decided to pep it up a little bit with technical help from Tom Langdon, America’s inline-six guru. He told me that a slightly larger camshaft, a four-barrel intake manifold, cast-iron exhaust headers, and a small Holley carburetor would make better use of the engine than did the stock setup. That and 3.73:1 rear-end gears. Best of all, I could improve power and efficiency without the annoyance of changing what I like to call powertrain infrastructure. Having done a V-8 swap before, I knew that while it’s not all that complicated, changing from one type of engine to another is not without its persistent list of annoyances and setbacks.
I haven’t finished the build yet, but the result is going to be a car that performs better than it did new, without the overpowering effect that so often turns lovely old cars like the Malibu into pretzels, courtesy of wet weather and some roadside tree. When it’s done, it will look more or less like it did when it rolled off the dealer’s lot and into the original faceless bureaucrat’s suburban garage: no chrome, no billet high performance parts, no problems.
There’s yet another advantage. An inline-six is no V-8, but when you think about the six’s lack of desirability and the corresponding availability of really cheap cores and parts, it begins to make a lot more sense. Add to that the fact that it can make plenty of usable power. People have been racing them for years, and racers have squeezed a lot of power out of inline-sixes with forced induction setups. Even without all that, the torque these engines produce makes for a very enjoyable street driving experience.
Beyond practicality though, there’s a measure of uniqueness that will appeal to the contrarian. Chances are good that you know someone who’s ripped a straight-six engine out of a car to replace it with a small block V-8, if you haven’t done so yourself. Either way, a lot of people have gone that route, often because scrapping an inline-six in favor of a V-8 has become a Pavlovian response of sorts (a lot like installing a big camshaft into an engine that’s otherwise stock, running big drag slicks on an axle equipped with highway gears, and myriad other bonehead moves). Here’s how it typically goes: Guy (or gal) sees a muscle car-era car or truck equipped with a six. Guy installs V-8. Guy sells running inline-six on Craigslist for $200.
But you don’t have to be like nearly everyone else. You can buck the trend and dare to be different. There are those who would argue that without the distinctive sound of an American small block, a project would fall short of expectations. To that, I counter that nothing sounds quite like an American inline-six. Uniqueness is sublime.
If you do decide to go the hot rod inline-six route, ask a lot of questions, even if the build is a mild one. With stock mills, factory service manuals usually suffice for repair and tuning help. But once you start changing things like the camshaft, carburetor, and exhaust system, you might need to seek technical advice from experts like Langdon, Tom Lowe, or the Inliners International enthusiast club.
While fewer people are involved in the inline hobby than digging into V-8s, they’re out there and they’re passionate. Diving into something that no one else understands has turned them into a tight-knit clan. Do you have what it takes to become an inline-six nut?