Project Miata

I have a 1999 Mazda Miata, its a great little car that gets good gas mileage for a sports car. I use this car for my daily driver during the spring, summer, and the begining of the fall. My goal with the mods that I'm planning is to enhance the air flow around the car. The first thing I did was to buy a magnehelic gauge off of ebay for about $10.



A magnehelic gauge can measure pressure differentials to a thousandth of a PSI. The importance of this is that a pressure differntial across a surface will insure that air flows through the surface. My plan is to seal the bottom of the engine bay to reduce the drag and also to reduce lift. To do this I needed to create an alternative path for the air to flow.




I decided to create a vent in the hood. First I measured the pressure differntial across diffrent points on the hood to find the area that would be optimal for air flow. The engine bay under the hood gets close to uniform pressure but the top of the hood goes from a high pressure zone at the front of the hood to low pressure along the flat surface and then back to a high pressure region at the base of the windshield. After i found the area that i wanted to cut my vents, i carefully measured and cut the 3 sides and then bent it down creating a vent. My next step will be to seal the area around the radiator so that the air that flows through the grill opening will be used for cooling and not just blowing through other openings.