Hello everyone,

As the stock throttle body can flow more than enough for a NA application, the intake manifold is the most restrictive point of our engine.
The goal of this post is to find a solution to implement the proposed improvement of the airflow for the stock intake manifold.


- The problem
The stock intake manifold is very restrictive internally.
It's chocking the engine at high rpm (it simply doesn't flow enough)



Internal view of the restriction


Cutaway of the intake (image from Honda 2009 Fit Powertrain - Media Newsroom Press release )



- The solution





- The implementation

We need to find a shop that can work with Plastics/Fiberglass to open the intake, cut the restriction and work the bottom/upper plenum.

Let's get the ball rolling and find an affordable solution to this problem.

I'm certain that this can unleash quite some power at high rpm.

 

No one is interested?

 

Why would you remove that,, it was put there as it equalizes air inside and to keep all cylinder get same air flow,, if you remove that one or two cylinder doesnt get enough air and youd have a rough revving engine

 

The 2 cylinder near the tb gets good air flow while the last 2 cylinder is fighting for air from the 2 cylinder near the tb

 

Power gains?!? I'd be shocked if that gave you anything.

 

I ported mine at home. Immediate improvement. There is a company in Turkey that does it if you send yours to them...