Let's Dig In to the Honda Civic OE Intake

Man has the time flown by!

We’ve been so busy working on parts, we forgot to lift our heads up to see what day it was. Sorry about that, but I swear it’s all to get awesome performance products out for your Honda Civic. 

Back in August we gave you a sneak peak at what’s in the pipeline for your Civic, as well as a more in-depth review of the 27WON Performance Exhaust for the Honda Civic Hatchback Sport. Today I want to tell you about the other side of the engine.

Let’s dig into the Intake System.

Airbox & MAF Non-Cutaway-wide.jpg

Oh and if you were feeling left out with the Performance Exhaust, don’t worry, the 27Won Performance Intake is designed for everyone with the Civic 1.5L Turbo. 

Like the exhaust system, I think it’s best that we start with the OE intake system to build an understanding of what makes it work and try to understand the reasoning behind Honda’s design. 



The OE intake system has many design aspects that need to be considered for a vehicle Honda expects to sell hundreds of thousands of and they each need to last at least 100K miles. Say it like that and it sounds like a tall order to fulfill, but let’s try to break it down to the essentials. 

First off, it needs to be cost-effective to produce hundreds of thousands of intakes. This means that the design needs to be able to be produced quickly, with minimal labor, and have a minimal number of parts. Honda nailed it. Like most OE manufacturers today, the intake system is intricate, yet has a minimal number of parts; two halves, a lower and upper portion, make up a majority of the OE intake system. These parts are injection-molded, which may have a high up front cost for the molds, but the cost to produce large quantities is extremely cost effective. On top of that, injection molding can produce precise and durable parts. 

Now enter the compromises… I mean "design aspects". We understand how a majority of the parts are manufactured, so now let’s look at how it all works. – Let’s follow the air through the system. 

Starting at the top, there is a rubber “scoop” that captures air from just under the hood at the core support.  Honda has done some simple and clever air flow control in an attempt to get cool ambient air from outside to the intake inlet. The scoop being rubber is a necessary aspect to prevent unwanted interference with the hood, but still provide a tight seal. We think there are other locations to source cool ambient air, but more on that in the next blog. 



The air enters the scoop then is routed to the back of the airbox, past a seal and into the lower half. This is where is gets interesting and intricate. 

The air has one major path to follow and one much smaller path to take. The larger path goes straight to the main chamber in the airbox before passing through the filter. The smaller path is routed to the bottom of the airbox to a port that goes into a chamber (not shown) that is very complex in design. I believe this is more or less a muffler for the intake system to cancel out specific frequencies and reduce the noise level; that doesn’t sound like any fun… we love turbo noises.

The purpose of these complex and purposeful air flow paths is to remove any concentrated moisture from the air; nobody likes a hydro-locked engine.

Now the dry-ish air is in the main chamber of the airbox and is ready to pass through the filter media to enter the Mass Air Flow (MAF) housing where the air passes over a sensor that measures the amount of air entering the engine. The diameter of the MAF housing is critical for the sensor to calculate the correct mass air flow. 

After the MAF housing, the air passes through a rubber hose with various accordion flex joints to allow the engine to move independently from the intake system. This accordion design can cause a lot of turbulence in the airflow which reduces the efficiency of the entire system. 

The many different turns, bends, flex joints and various necessities to create an intake for the masses takes its toll on performance. 

It may not be a major concern for stock power, or maybe even a light tune, but when you start really trying to push the performance of the engine, a new system will be needed. 

Next time, we dig into the design and development of the 27Won Performance Intake for your Honda Civic.

Thanks for tuning in with 27Won Performance.

I dare YOU to Redefine The Aftermarket

-Barett @ 27Won Performance