How Ferrari Got 819 HP and 9500 RPM From a 6.5-Liter NA V-12

1622671532 screen shot 2021 06 02 at 9 34 34 am 1622641208
1622671532 screen shot 2021 06 02 at 9 34 34 am 1622641208

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The 812 Competizione may use a formula that dates back to Ferrari’s very beginning— a naturally aspirated V-12 driving the rear wheels of a two-door two-seat GT— but you can’t call this car (and its convertible sibling, the Competizione A) old-school. Like all modern Ferraris, it’s about as high-tech as performance cars get, with all sorts of clever engineering details to pore over. To understand the Competizione better, we spoke with Michael Leiters, Ferrari’s chief technical officer.

Inarguably the highlight of the Competizione is its V-12, a 9500-rpm, 819-hp, 6.5-liter version of Ferrari’s long-running F140 mill. If you’re wondering how Ferrari managed to extract 9500 rpm and 819 hp from a big engine without resorting to forced induction or electric augmentation, well, so were we. Leiters and his team employed a number of techniques, but perhaps the most important is the use of finger followers in the valvetrain rather than employing typical bucket-and-shim tappets to open the valves.

ferrari 812 competitizone v12

Ferrari

If you’re not familiar, that’s fine, as there’s only one other road car in production using similar hardware, the Porsche 911 GT3/GT3 RS. Finger followers are more common in race engines and sport bikes; conveniently for us, Cycle World legend Kevin Cameron has a typically excellent explanation of what they are and how they work. Observe:

“When it becomes necessary to make valvetrain parts as light as possible to allow operation at high engine rpm and/or high valve acceleration rates, the finger-type cam follower is the best choice. It is a lever, pivoted at one end with the other end bearing against the end of the valve stem, and it is in no part wider than the cam lobe. Facing the cam lobe is a smoothly ground curved pad, given great surface hardness to resist wear. As the cam lobe presses against this pad, the moving end of the lever pushes against the valve stem, opening the valve.”

Leiters said that it’s possible to achieve a 9500-rpm redline in this V-12 by using traditional tappets, but the wear on those parts would be unacceptably high. Plus, it’s always good to reduce engine weight wherever possible. Still, for all their benefits, finger followers are typically quite expensive and complex to produce, which is why you don’t see them often.

Cutting weight and strengthening the rotating assembly was also critical. So many components, including the cams, finger followers, and crankpins, were given what Ferrari calls a diamond-like carbon coating. The V-12 now sports titanium connecting rods that are 40 percent lighter than the steel units previously used, and the pistons and crankshaft have been redesigned as well.

ferrari 812 competizione

Ferrari

Of course the higher an engine revs the more power it makes. As noted, the V-12 in the Competizione makes 819 hp at 9250 rpm, compared to 789 hp at 8500 rpm in the standard 812. But Leiters insists that, while there was a need to increase horsepower, it wasn’t the primary consideration for increasing the redline. “Apart from the performance, for Ferrari, it is more important to create unique driving emotions,” he said. “Therefore, 9500 RPM was our center point of our project.”

Ferrari also had to install gasoline particulate filters in the Competizione’s exhaust system to meet upcoming European emissions regulations; these filters typically reduce sound. Leiters estimates it was around ten dB in this case, but more important than the loss of volume was the loss of those high-frequency tones that define the modern Ferrari V-12 sound. “We don’t want to make noise,” Leiters says. “We want to make music. We have to recover the quality of the sound. The particulate filter works like a damper. Unfortunately, it canceled the high orders of the engine, and these are the orders you need to accomplish that thrilling sound.”

Part of the solution was simply getting rid of the mufflers, but Leiters said that Ferrari also developed new oval-shaped exhaust tips which work something like a trumpet. They reside on either side of a new and much wider diffuser, and in addition to providing excellent sounds, they also interact with air coming from underneath the car. Letiers is hesitant to call this a blown diffuser, however, though Ferrari says the concept is definitely Formula 1-inspired.

As we’ve come to expect, the 812 Competizione features a number of aerodynamic and chassis upgrades over the Superfast, but the one that stands out is the rear-wheel steering system. Ferrari began using rear-wheel steering with the Competizione’s predecessor, the wild F12tdf, and refined the system significantly for the 812 Superfast. All four-wheel steering systems have the ability to steer the rear wheels in either the opposite or same direction as the fronts, but the system in the Competizione can also steer either rear wheel independently of the other.

That sounds like it would feel unusual, at the very least, but Leiters says it was implemented to make the car feel more natural and thus confidence-inspiring. Ferrari calls its four-wheel steering system Passo Corto Virtuale, or virtual short wheelbase, because when the rear wheels turn in the opposite direction of the fronts, it has the effect of making the car behave as if it had a shorter wheelbase. Leiters says that this new system will more aggressively turn the outside wheel in a corner while keeping the inside wheel relatively straight. “When you have a shorter wheelbase, the car is getting more responsive, more agile, but also more nervous,” Leiters says. “So, we are now getting this effect without getting a nervous car.”

Modern Ferraris typically have an incredibly sharp and responsive front end. However, in the F12tdf especially, and the Superfast to a lesser extent, this amazing turn-in makes the rear feel loose. This new rear-steer system is designed to give drivers confidence that the rear is following the front without losing that hyper-sharp contemporary Ferrari front end. And Leiters says the system isn’t programmed to do anything the driver wouldn’t expect; it’s only reacting to what the front wheels are doing.

There’s obviously a lot more to talk about, and we’ll certainly do that once we get the chance to drive the Competizione. But let this be proof that, while a front-engine V-12 GT car might seem like an anachronism, the Comptetizione is anything but.

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