Custom Cold Air Intake

1
Custom Cold Air Intake
2
The Problem

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

3
Experiment

• Can engine performance be boosted by decreasing
  inlet air temperature?
• Can this be done with simple ducting to the
  firewall?

4
Experimentation Process

• First the stock snorkel is removed from the
  airbox.
• A new hose is connected to the airbox (2.5 inch
  shop vac hose)

5
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.

6
Experimentation Process

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

7
Results

• 5. Temperature measurements were made at the
  stock air intake location and compared to the new
  cowl intake location.

Cowl Intake Temperature 47.2 F
Stock location 109 F
A 62 Difference!
8
Results
9
Results

• Stock miata dyno chart

Image taken from www.flyinmiata.com