Project S2000: Part 20 – Stock Air Box Modifications And Not Going Faster

Project S2000: Part 20 – Stock Air Box Modifications And Not Going Faster

by Khiem Dinh

Khiem Dinh is an engineer for Honeywell Turbo Technologies at the time of this writing.  All statements and opinions expressed by Khiem Dinh are solely those of Khiem Dinh and not reflective of Honeywell Turbo Technologies.

After testing the ram air/cold air NACA duct in Part 19, I noticed a trend in the intake manifold pressure where it drops as the engine approaches redline. A member of one of the forums had commented on some of his own testing showing that removing the lid of the air box resulted in less pressure drop. He had used a pressure gauge attached to the intake tube common on off-road trucks to gauge when the air filter is dirty. So this got me looking into the guts of the stock air box. Was the 90 degree internal tube a flow restriction?

 

Using my practically non-existent Photoshop skills, this overlay shows just how much space the stock cone air filter takes up in the air box. Yeah, the Honda engineers took up all the space they could.
With the lid cracked open, you can see how the internal snorkel aligns with only a fraction of the air filter. Is there opportunity to better use all that air filter surface area?
I stuffed the camera in the air box, put on the timer and closed the lid. You can see how the snorkel does sit a fair amount away from the filter.
With the lid shut, it seals up the internal snorkel very well with the internal divider wall in the air box.

Leave a Reply

Your email address will not be published. Required fields are marked *

*
*