FL5 Air Intake Design Blog PT.2 - Elements of a Performance Intake

Some time has passed since our last dive into the intake system design for the latest 2023+ Civic Type R & Integra Type S but that doesn’t mean things have been quiet. In fact, we’ve been collecting tons of data and hammering out design details for our own 27WON system and today, I want to share with you some of our progress on that and also what comes next. So, buckle in and get ready for the ride.

There are three main components to design for our FL5 intake. A MAF housing, a silicone filter mount, and a shroud to keep hot engine air away from the filter. We’ll focus on the MAF and Shroud primarily here.

One challenge with the FL5 is that the intake tract between the turbo inlet pipe and the OE airbox is very short.

This limits space for a nice big air filter. For this reason, you’ve seen some companies respond with odd shaped or small (Pancake) filters. In trying to come up with more space for the filter we figured out a new MAF design we are pretty proud of. Our MAF housing concept eliminates one piece of silicone altogether and a hose clamp interface by using a unique twist and lock design. This also frees up space for a nice large filter (more below)

Below you can see a mock-up of the MAF to filter stack-up.

This is what the design looks like installed with some prototype 3D printed parts and a filter.

You may notice that even with our innovative MAF design we still had to shift over the ECU to get enough space, but we’re able to utilize a nice large dry-flow filter element that doesn’t sacrifice flow.

Another area and by far the most difficult in developing so far on our FL5 intake has been the shroud. Here is a model of the design from a few iterations ago

And here is a very early mockup of a 3D printed prototype in the car.

The shroud needs to block hot air from the engine as much as possible. This means it needs to seal against the hood well and prevent hot air from leaking around the battery and ECU. In this early design we were exploring retaining the OE hood seal. Ultimately, we abandoned this approach but this should give you some sense of the things we considered during design. 

We’ve done a lot of data logging and testing of this intake system already, especially around the shroud design in an effort to achieve OE like intake air temps, but with much more flow potential. We’ll share some of what we learned in our next blog in this series as well as some pictures of samples! 

As always, thanks for tuning in fam and till we meet again!

-Rich

Co-Founder
REDEFINE the Aftermarket