27WON Performance

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No Turbo No Problem - 11th Gen Civic Intake for Naturally Aspirated Engine Design Blog Pt. 1

Nearly every engine performance part we have designed and created thus far has been for a factory-turbocharged Honda Civic or Acura Integra. Parts like our Big Brake Kit and Front Strut Tower Bar can cross many chassis despite the engine differences but an item like an intake air system is specific to the engine.

You read our blogs and we read your comments AND so WHEN a commenter by the name of “RP” asked for a K20C2 SRI ON our 1.5T SRI blog, WE ANSWERED THE CALL.

For this blog then, we start off by looking at the OEM intake system for a naturally aspirated (NA) 11th gen Civic equipped with the K20 and then we share a bit about our take on a performance intake upgrade.

The first thing to note is that since a NA car is without a turbocharger the intake system connects to the throttle body instead of a turbo inlet pipe.

Now despite being NA, the overall intake design is pretty similar to a turbocharged Civic. At the start, there is an inlet that is taking in outside ambient air. From there a rather large airbox with bends and curves, a paper media filter, MAF housing and sensor, a flexible intake tube, and various hoses and tubes for EVAP stuff. We see the usual materials like molded plastic for the airbox, rubber for the intake air duct, and the same MAF sensor as the L15 Civic (turbo).

Despite the similarities, two things stick out to us here at our development center.

Look at the size of the air filter. It is both rather small and rather greedy. What do I mean by greedy? Well, because of how the air enters the bottom of the airbox the air primarily goes through one corner of the filter. Rather than using the whole filter more evenly, the small hole at the bottom of the airbox feed makes the air hug one side. This leads to an air filter that needs to be changed out earlier and can limit power production. Check out the images showing the air filter has more contaminants on it when compared to the rest of the filter and you can see the air inlet inside the red circle.

The next thing that came to our attention is just how big the OEM system is. The picture you see above is only half the airbox. There is still a whole other resonator piece that attaches to the bottom of it that aims to make the stock intake as quiet as possible. The only reason you don’t see it in the picture is, well frankly, it's a pain in the @$$ to take it out so we left it in there. Our intake design won’t be using that part of the airbox so it will be up to you if you want to leave it in there or take the time to dig it out. 

The crew here at 27WON is aiming for a simple and effective SRI, at a great price point, for our first non-turbo Civic intake system.

A nice 4-ply cone air filter will be used to fix the crowding problem of the OEM unit. Its 360 degrees of surface area and being opened in the engine bay will allow the intake to move more air. We are designing a brand new MAF housing to make sure all the fuel trims are dialed in and to make sure we can provide great value with this intake. Lastly, our zero step-down silicone will have the air flowing as smooth as possible into the throttle body.

This combination of features helps maintain and can even provide lower IAT’s when the car is in motion. Lower IAT means more power. Pretty simple.

We have not even mentioned the best aspect of this intake. It sounds awesome!

We are validating pre-production parts already and we hope to have this intake to market by the end of the year.

Stay up to date by reading all of our future blogs on this product and many more right here. Till next time!

REDEFINE the Aftermarket
-Vincent 

Co-Founder