Honda’s latest K-series engine, the compact but potent Civic Type R’s K20C1, could be tuners’ new favorite swap.
There’s no denying it; the FK8 Civic Type R is one of the best hot hatches out there recently. Why? The secret sauce lies under the hood — Honda’s K20C1.
The K20C1 is a 2.0-liter inline-4 turbocharged engine, part of Honda’s K-series engine family. It was first introduced in the FK2 (4th-gen) Civic Type R in 2015 and was carried to the following model, the FK8 currently on sale.
Interestingly, many argued that the K20C1 would never live up to the superb power units used on previous Type R models such as the B16B or K20A. However, it’s now clear that this new engine is a legitimate successor to those legendary mills; and I must say a worthy one.
But what really makes the K20C1 stand out from the crowd?
Let’s discuss.
The K-Series Engine
To understand why the K20C1 engine is the new talk of the town, it’s essential to start with the K-series as a whole, which included some of the most refined engines Honda ever produced. The first model introduced in 2001 in the Civic and Integra Type R models and now present in many common Hondas/Acuras was nothing but a game-changer — it might not have looked like it at the time, but in retrospect, it surely was.
Of course, on paper, the first K-series engines may not have looked like they would be worth any special high-performance award. With a modest redline and no turbocharger, the initial K-series unit gave the impression of just another 4-cylinder engine built to power econoboxes and provide excellent gas mileage. However, these engines were engineered to perfection, which could only be a telltale sign of better things to come.
In the following years, these robust engines were then made available in some of the best-selling vehicles worldwide, allowing Honda to gather tons of valuable data and use it to improve them even further, working hard to turn them into truly mean machines, worthy of standing side-by-side with hard-to-beat predecessors such as the B-, D-, and F-series.
The Retention of VTEC
Much like most successful Honda engines of the past, the VTEC (Variable Valve Timing & Lift Electronic Control) system is still here. Contrasting the “regular” variable valve timing system found in its competitors, Honda’s VTEC is the jack of all trades, providing lower fuel consumption at low RPM and higher performance at high RPM — a winning recipe for sure!
But if that wasn’t already enough, in K-series engines, Honda uses an i-VTEC (intelligent-VTEC) system combining VTEC with Honda’s VTC (Variable Timing Control) hydraulically operated camshaft system. The two systems make for a great combo since the VTEC part controls the valve lift and duration according to the low/high RPM profiles, while the VTC allows for the continuously variable camshaft phasing throughout the RPM range.
As a result, the two systems working in unison offer a better balance between performance and efficiency, while also providing a much better torque distribution across the range — in short, it pulls harder and longer.
Welcoming the Turbocharger
The K20C1 is the first Civic Type R engine to come equipped with a turbocharger. However, this wasn’t the first appearance of a turbo in a K-series, as the 2007 Acura RDX’s K23A1 unit was the first to receive this treatment. Although that engine had quite a lag resulting in rather erratic power delivery, it inspired the Japanese manufacturer to produce more (and better) turbocharged engines.
In 2013, Honda released the VTEC Turbo engine series. As a part of its Earth Dreams Technology range, these engines come stock with a turbocharger, direct injection, and dual cam VTC. Unfortunately, since they now featured VTEC on the exhaust instead of the intake, petrolheads had no other choice but to say goodbye to the VTEC’s signature sound. But, this VTEC implementation on the exhaust rocker arms resulted in the turbo spooling quicker, significantly reducing turbo lag — kind of a blessing in disguise here.
All that to say that the K20C1 is currently the top engine in the VTEC Turbo lineup, producing over 300 hp @ 6500 RPM and 295 lb-ft @ 2500 RPM in its stock form, not bad at all for a rather small inline 4. Moreover, it’s also Euro 6 compliant, making it the most environmentally friendly Type R engine yet (not that anyone would ever buy a K20 solely for this reason but you know, just thought I would mention it, lol).
What is the K20?
Honda initially started its K-series with the K20A, produced specifically for the Japanese Domestic Market (JDM). The high-performance version of this powerplant found a home in some joyous little rockets like the EP3 and FD2 Civic Type R, DC2 Integra Type R, and Accord Euro R. Later on, Honda produced seven other variants of the K20A, including the K20A1, K20A2, K20A3, and so on, which finally found their way into the US market. Honda would continue making the K20A series until 2011.
Meanwhile, back in 2005, Honda also started the production of its K20Z engine, consisting of five engines quite similar to the K20A’s. indeed, they’re also naturally-aspirated 2.0-liter 4-cylinder units with roughly the same power and torque outputs and offered in some fun Honda cars, like the 8th gen Civic Si and Acura RSX Type S.
At last, 2015 arrived, and Honda discontinued the K20Z series, adopting the K20C series instead, six new powerplants more powerful than ever. Almost all of them featured a turbocharger, direct injection, and VTEC on the exhaust valves. However, the star of the show here is undoubtedly the K20C1, the beating heart of the now-iconic FK2 and FK8 Civic Type R.
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Honda’s K20C1 Engine
Of course, installing a turbocharged engine in the Civic Type R might’ve been a gamble. With a redline barely reaching 7000 RPM and the absence of that “VTEC-kicked-in-yo!” feel, it simply didn’t sound like the Type R we used to know — it was a new breed altogether.
But the K20C1 had a few things up its sleeve to make up for it.
Engine Details
The K20C1 is arguably the most hardcore and sophisticated K-series engine ever produced. Indeed, thanks to the aluminum block and head, forged steel crankshaft and connecting rods, an exhaust manifold integrated within the cylinder head with direct access to the turbocharger, it’s more than ready for a fight.
To lower the piston rings’ temperature and keep the pistons cool when pushing the engine to its limit, Honda chose to go with F1-style internal cooling galleries and specially designed oil jets located inside the cylinder block. Consequently, it’s safe to assume Honda wasn’t aiming for a discrete daily commuter here. Moreover, the K20C1’s chain-driven dual overhead camshafts are made thin-walled and hollowed-out to reduce rotational inertia for better acceleration from a standstill. Meanwhile, the low-friction timing chain is long-lasting and doesn’t require any necessary maintenance — thumbs up for Honda on that.
VTC on both the intake and exhaust camshaft makes valve phasing possible. However, as mentioned earlier, the i-VTEC system is only present on the exhaust cam and not the intake since the turbo setup eliminates the need for the additional lift to push air into the engine. Yet, the exhaust cam uses the VTEC to reduce exhaust gas resistance, enabling a higher lift cam profile and bringing those exhaust gases out at higher RPMs.
In short, the K20C1 engine might be compact and small, but every little bit is designed to put out the best performance possible, without sacrificing fuel efficiency and reliability — Honda at its best, ladies and gentlemen!
Type R Powerplant
The K20C1 power unit was made specifically for the Honda Civic Type R and first appeared in the 2015 FK2 model, boasting 306 hp and 295 lb-ft of torque. Like all turbocharged K20C engines, it has a 9:8:1 compression ratio, lower than non-turbocharged past VTEC engines. Even so, it claims the highest power output ever generated by a stock Civic Type R.
In 2017, Honda carried the K20C1 power unit into the next-gen FK8 Civic Type R, outputting the same power and torque as the FK2, except for the European and Japanese markets, where it generated 10 more ponies.
Both the FK2 and FK8 versions of the engines were paired to a 6-speed manual transmission, driving the front wheels. However, the FK8’s gearbox was even better, featuring rev-matching control to help you shift gears like a pro — no need for heel-toe downshifts here.
Still the Darling of Tuners
Any wise mechanic would advise you to start with a good engine as a base for any of your projects, and the K20C1 is undoubtedly an up-and-coming candidate. With a solid build, decent stock power output, and outstanding reliability, it’s hard to make the K20C1 less attractive to modern-day tuners and builders, especially if they used to love the good ol’ B- and D-series.
Modular changes to engine characteristics like the compression ratio, VTEC system, and rotating assembly optimize the standard engine for power, fuel economy, and anything in between. Moreover, tuners are blessed with the almost Lego-like ability to change and swap different engine components and create a unit perfectly suited to any driving style.
As a result, upgrading the K20C1’s power output is as easy as any other Honda engine of the past. With just a few bolt-on mods like a cold air intake, front-mount intercooler, complete exhaust system with downpipe, and a bit of ECU tuning, you can easily expect to pull over 400 hp and 400 lb-ft out of it, and that while keeping the stock turbo. In fact, an American tuning company called 4 Piston Racing proved that the K20C1 could easily make a lot more, building the engine into an 800 hp beast.
Engine Swap Culture
One of the best things about Honda’s performance engines is their ability to fit into pretty much any other Honda model (might be pushing it with the S2000, though). Swapping out an old 90’s Civic, CR-X, or Integra engine with the fresher K-series unit has been a common phenomenon, creating unique cars with that retro feel we love so much but incorporating some of that modern tech under the hood. Not only is it reasonably easy to do (assuming you’ve got the skills to do it), but these engines also have a lot of potential.
With the K20C1, Honda even encourages engine swaps by offering it as a crate engine in the US, strictly for sanctioned racing applications (wink-wink). It’s a moderately priced solution for those who want to convert their regular Civics into a true race car (or a street fighter if that’s your style — Honda doesn’t need to know, right?).
Not to forget that the K20C1’s toughness has already been well-established by purpose-built race cars using it to participate in BTCC, IMSA, Road to Indy, and many other forms of endurance racing.
And if it’s good enough for endurance racing, it should do just fine for those occasional weekend track days.
Last Words
The 4th- and 5th-gen Honda Civic Type Rs are interesting performance-oriented cars for so many reasons, the super solid K20C1 engine being the most prominent one. With this impressive power unit, Honda has proven that modern VTEC turbo engines can be as fun and engaging as its naturally-aspirated mills from back in the day.
Despite the rather modest redline and lack of signature VTEC vibe, the K20C1 delivers more power, improved response in the low-end of the band, and much better fuel efficiency (which is not to neglect with gas prices these days). Also, it retains Honda’s legendary reliability and the upgradability trait of its older counterparts that we loved so much.
With plenty of evidence of its excellent performance, it’s safe to assume the turbocharged direct-injection K20C1 could be the Honda engine that tuners and builders will work with for the next 10-20 years.
In short, if you don’t already have one, get one!
Already have one? Get another!
We might be better off stocking up on a couple of those before electric cars finally take over. At this point, you’ll be quite happy you’ve got them, even though the VTEC doesn’t really “kick in” anymore!
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