k20

Every superhero has a weakness or villain thwarting them at every turn. Superman has those glowing alien rocks. Batman is constantly putting out fires both figuratively and literally set by some deranged clown, and the internal combustion engine has its respiratory system clogged up by its own lifeblood. Yes, we're talking about blow-by. Granted, carbon buildup from blow-by might not seem as serious as the threat of a supervillain, but it's an affliction that affects every engine out there, even your new Honda Accord.

The 2018 Honda Accord 2.0T might not be flying around Metropolis or Gotham punching criminals in the face, but this generation of Honda's full-sized sedan is taking the heroics of daily driving to a new level. Utilizing the K20C4 derived from the heavy-hitting Civic Type R, Honda ditched the V6 for some efficient and punchy direct injected and turbocharged attitude all under an aggressive new skin dripping with tech.

In this day and age, it's not very common to still see three

Intakes are typically the first modification that any automotive enthusiast would recommend in the name of quick power gains. It's really no surprise either. If you take a look at any modern vehicle on the road today, including the Civic Type R, stock intakes are full of silencers, restriction points, and accordion-style hoses. Those are three things that I know every gearhead doesn't want, and in fact it's quite the opposite when looking to add some power, so we've been researching solutions to get rid of them.

To start, let's briefly revisit our stock air intake. While the Type R is based on the return of the Civic hatchback to the US, it's no regular Civic hatchback. The beefed up aerodynamics on the exterior, and bright red racing seats, have the 305hp K20C1 to match, which includes a well-thought-out intake system. From the factory, Honda included a cast aluminum runner which not only accounts for 2/3 of the stock system, but also does most of our jobs for us. We only needed to focus

Engine blow-by is something that affects just about every engine on the road. Though plenty of manufacturers have made leaps and bounds in filtering blow-by from the intake, finding clever ways to keep the carbon deposits from building up on intake valves, blow-by remains an issue. This should come as no surprise if you've spent any time on our blog. Just about every type of car and truck that has made its way into our R&D facility, ranging from BMWs to F-150s, and even the 1.5T found in the base Civics, have all produced varying levels of the murky stuff. The K20C1 is likely to be no exception to this trend. That leaves it up to us at Mishimoto to make sure none of the contaminates in the crankcase gasses make it to your valves.

Our Championship White loaner on the Dynojet for baseline testing.

When we last left off, we were too impatient to wait for a CTR of our own, so we got in contact with a local owner to get a jump on some of the items for the Type R, one of which being a catch can.

It's finally here. After 20 years, and a few extra months of waiting, the Civic Type R has made its way to the States. I have to say, if the standard Civic wasn't striking enough, the Type R has the qualities to make it one scalding hot hatchback. While some of the components carried over from the last generation, including some of the aerodynamics and the return of the mighty K20C1, the FK8 actually went on a bit of a diet and received not only a cosmetic makeover, but also a suspension overhaul fit for the new king of the Nürburgring. It's easy to see why so many are willing to pay thousands over MSRP for the chance to call this new Civic their own.

Something about that wing lets you know that the CTR means business.

There is no denying that the Type R is a performer almost on the same level as premium Porsches or BMWs; and like all performance machines, these cars only perform well if they are maintained. Yes, I'm going to be that guy and talk about maintenance on the hottest hatchback

We've got another awesome project in the works for the 8th-generation Honda Civic Si! Our recently released performance intake system received great feedback from customers, but it also identified an additional need for intake system components. We decided to develop a Civic Si induction hose made from silicone to replace the stock rubber unit.

Stock Civic Si Induction Hose

Before jumping into the design of our prototype hose, check out a few shots of the stock unit.

Stock Honda Civic parts

Stock Honda Civic parts

The stock hose directs airflow coming through the airbox/mass air flow (MAF) housing to the throttle body. This hose has quite a unique route around engine bay components. Two separate flex joints on this piece allow for the engine movement. These areas of the hose are typically prone to cracking and splitting from oil saturation and extended exposure to heat. This hose features two crankcase ventilation (CCV) connection points that will need to be replicated on our design to

Interested in purchasing our new Civic Si intake system? Check out more details on our product page linked below!

Mishimoto Honda Civic Si Performance Air Intake

Our last write-up for this Civic Si intake included our dyno testing results as well as some insight into our use of 3D printing for rapid prototyping. Since then, we've tweaked our design to provide flawless fitment and we've constructed a final prototype. The last box to check on our list is a final fitment verification and road testing. Our test vehicle owner will be putting some additional road miles on the car and will offer his opinion of the improved intake sound. Soon we will have a new addition to our line of Honda Civic Si parts!

Final Prototype

Mishimoto Honda Civic Si final prototype parts

As we've mentioned previously, this kit is a drop-in replacement for the stock setup. We will include all components needed for installation.

One of the key pieces to this kit is the aluminum intake pipe. Check out a closer look at

Interested in purchasing our new Civic Si intake system? Check out more details on our product page linked below!

Mishimoto Honda Civic Si Performance Air Intake

Now that we had a functional prototype, it was time to perform some dyno testing to ensure that we were on target for producing a power-adding intake system. The dyno results would provide some base-line data so we could move forward with refining our intake design.

Dyno Runs

We quickly strapped the Si onto our Dynojet in preparation for our day of testing.

Honda Civic strapped to Dynojet for intake testing

Honda Civic Si strapped to Dynojet for intake testing

Of course we did some filming during our dyno runs to capture differences in intake sound from the stock Civic Si intake to our prototype. Check out the video below!

Testing Results

Our initial test simply captured power output while monitoring AFRs to ensure that they remained within a safe margin of the stock intake.

Check out the dyno plot from this test!

Dyno plot for

Interested in purchasing our new Civic Si intake system? Check out more details on our product page linked below!

Mishimoto Honda Civic Si Performance Air Intake

Stock Si engine bay

With a K-series power plant, 6-speed manual transmission, and a limited slip differential, the Si is a great choice as a fun commuter that can double as an autocross machine on the weekends. As with any performance vehicle, more power is always on the minds of enthusiasts. Mishimoto has been working to develop brand-new intake systems for a variety of vehicles, and the 8th generation was next on our list for some R&D.

Getting Started

We started with a blank slate on this project. We researched the type of intake we wanted to design as well as where we would place the filter. A true cold-air system would have the filter in the driver-side fender well. Our team investigated the details of installing a true cold-air setup (filter within the fender well) and found the process to be quite extensive. While some DIY