66 out of 100. That might not sound too impressive, but when it comes to the top 100 Nürburgring lap times, any manufacturer would be honored to even make the list. 66 is where the current Civic Type R sits with a time of 7:43.8, making it the fastest front wheel drive car to hit this notorious 12-mile stretch of track. If you scroll though the list, you’ll only be able to find a few other FF cars peppered in with all of the Porsches, Bimmers, and countless exotic hypercars. You might also notice that the CTR has made back-to-back appearances in the top 100, which is an impressive feat for any company that isn’t Porsche apparently. By this point though, I’m sure you’ve all already heard the news about the record setting lap time. What the world of new CTR owners want to know is, “How do I make it faster?”
With Honda’s K20C1 delivering power figures of 298HP and 304ft-lb of torque from the factory, one would assume that this hardcore Civic is nothing but maxed out. However, in the name of assembly costs, and comfort to the end consumer, the Type R was equipped with a few restriction points. Two of our top three projects for the CTR involve removing those restrictions, including the intercooler and airbox.
The Type R’s stock intake is a well-thought-out breathing apparatus for the 2.0L turbo. Typically, when we open the hood to start working on intake projects, we’re faced with a combination of rubber and plastic as housing to send the air to the turbo. This is the Civic’s cream of the crop, though, and Honda minimized their use of these materials. Between the turbo and the rubber boot, the engineer utilized an aluminum intake hose, which makes for a smoother flow of air. In addition, the metal construction does wonders for the durability of the system.
Since Honda pulled out all the stops for the CTR, we only need to focus on what’s attached to the end of the aluminum intake pipe. Clamped on is a rubber boot separated by a plastic elbow, all leading to the airbox, which is seemingly affixed to the front bumper. The aerodynamics are half of what makes this car so quick around the ring, so Honda didn’t want to waste any of the airflow passing through the multitude of slots and grilles incorporated into the design. To capture all this precious airflow, a rubber boot—or snorkel—is fixed to the top bumper panel with some serious weather stripping to make sure that some the air flowing over the engine bay is funneled through the filter. To get a closer look at the stock airbox, we decided to remove it.
I have to say this might be the most peculiar looking airbox I’ve come across. The box’s profile, with the rubber boot still attached, is reminiscent of a French horn. The unique shape of the box is thanks to a few different reasons. First, while the CTR is a serious asphalt devouring track monster, Honda intended it to be comfortable for everyday driving as well, which means sticking to the stringent noise, vibration, and roughness tests. One of the common byproducts of these assessments is an air straightener, most used to muffle the sound of the intake air, something the everyday driver might find as a necessity, but a restriction to performance and the full experience of the car.
The airbox’s shape is also due to Honda’s choice in filter style. The flat panel air filter is the first, and in a majority of manufacturers, the only choice when it comes to intake filtration, mostly because they’re fairly cheap to produce and only require a slight maintenance obligation from the owner. However, the fresh air now has to enter through the bottom of the airbox and pass up through the filter before travelling to the engine, which explains the rubber snorkel.
After passing through the MAF housing, this fresh, and now filtered, air has to travel through the only other bits of plastic and rubber before entering the aluminum section of the intake. Unfortunately for the sake of performance, it needs to pass through an accordion-style rubber hose, plastic elbow, and another rubber coupler before it can get there. These materials are known for wearing and degrading over time, and the interior texture of the hose is detrimental to the uniformity of the airflow.
While, on the whole, the CTR’s stock airbox is fit to fill the role of daily driver and track king, it unfortunately still suffers from these few weaknesses. Luckily, our intake guru, Ye, is on the case and honing in on these shortcomings to help unleash the Type R’s full potential. Be on the lookout for the next post containing some seriously techy stuff from our flowbench testing.
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