Custom Cold Air Intake

The Problem

• Due to the location of the existing intake, hot air is being drawn into the combustion chamber.

Experiment

• Can engine performance be boosted by decreasing inlet air temperature?

• Can this be done with simple ducting to the firewall?

Experimentation Process

1. First the stock snorkel is removed from the airbox.

2. A new hose is connected to the airbox (2.5 inch shop vac hose)

Experimentation Process

3. A 2 inch hole is made in the firewall as pictured below. This area is referred to as the cowl. It is a high pressure area where colder air can be accessed.

Experimentation Process

4. Finally the airbox is reinstalled with the new hose and connected to the cowl.

Results5. Temperature measurements were made at the stock air intake

location and compared to the new cowl intake location.

Stock location – 109° F Cowl Intake Temperature – 47.2 ° F

A 62° Difference!

Results

Results• Stock miata dyno chart

Image taken from – www.flyinmiata.com