At EngineLabs, we are fans of the internal combustion engine in all its glorious iterations. While we mostly focus on domestic V8s, we by no means have blinders on to the rest of the spectrum of engines. As such, we bring you this video, chronicling nine of the largest inline four-cylinder engines ever produced for four-wheeled automobiles.
While inline fours are generally thought of as small, high-winding engines powering fuel-efficient commuter cars, in fact there have been a number of large, robust inline-fours that displace serious cubes and make some respectable torque. Generally, this comes from the fact that in order to increase displacement, the designs are usually undersquare, with a long stroke, lending themselves to low-RPM torque.
The GM LLV (or Vortec 2900) is definitely the most modern of the big four-cylinders on this list.The now-discontinued Chevrolet LLV, also called the Vortec 2900, was part of the GM Atlas line of inline engines, which included four-, five-, and six-cylinder designs. The big four-cylinder has a 3.76-inch bore, with a 4.00-inch stroke to come in at just over 2.9 liters, or 178 cubic inches. Even with the long stroke, it still made power higher in the RPM range than one might expect, with its 185 peak-horsepower happening at 5,600 rpm, with a 6,300-rpm rev limiter to go against the norm for big four-bangers.
The Pontiac “Trophy 4” inline four-cylinder was a relatively short-lived design, only produced between 1961 and 1963, but at 3.2 liters, or almost 200 cubic inches, was a stout engine. Basically half of Pontiac’s Trophy V8 engine, it shared the same 4.125-inch bore and 3.75-inch stroke (along with quite a few mechanical components) making it the only oversquare big four-cylinder on this list. The engine was developed by John DeLorean, so it’s fitting that it powered his other brainchild of the time, the Tempest. When fitted with the factory four-barrel carburetor, the “Power Pack” variant made a whopping 166 horsepower and somewhere north of 215 lb-ft of torque.
The 200.5 cubic inch (3.3-liter) Ford L-Head managed to squeeze out a whopping 40 horsepower from its 3.876-inch bore and 4.250-inch stroke, but got between 25 and 30 miles per gallon in the Model A and Model AA variant vehicles, while an upgraded version lasted two years beyond the Model A alongside the then-new V8 engine, the Flathead Ford. While not a spectacular engine, it does occupy a significant seat in history; besides being one of the largest four-cylinder engines in automotive history, it was also one of the designs that helped shape the face of mass-produced engines.
Not a whole lot of information exists on the Fiat Tipo 55. However what we do know is that the engine powering the base 1912-1916 Tipo 55 was an 8.5-liter (almost 522 ci) inline-four-cylinder that made in the neighborhood of 60-75 horsepower. There was a “Speed Car” variant, which had a 9.0-liter four-cylinder engine, and was guaranteed to hit 70 miles per hour straight off the factory floor. That was an absolutely incredible accomplishment in the pre-WWI era, and very few of the speed cars are known to exist today.
Finally, we come to the largest four-cylinder to ever grace an automobile chassis, and that’s the “Beast of Turin”, the Fiat S76. This should be no secret to EngineLabs readers, as we’ve featured its revival video, along with its appearance at the Goodwood Festival of Speed. However, for those unfamiliar with it, this beast was produced in 1910 with a massive 28.5-liter (1,730 cubic inches – no the decimal isn’t in the wrong spot) four-cylinder engine. The undersquare 190mm (7.48-inch) bore and 250mm (9.84-inch) stroke produced a whopping-for-the-time 286 horsepower and an unbelievable 1,991 lb-ft of torque. It has three spark plugs per cylinder and a low-voltage magneto for the ignition, and as you can tell from the video, could use an ignition box upgrade something fierce.