Last updated Monday March 26, 2012

Grill Block and Air Dam

Friction is ultimate energy waster and contributor of finite range.  

If you can reduce or maybe even eliminate the friction, a vehicle could travel for any distance, forever on its own momentum.

Air friction (at freeway speeds) accounts for 30-60% of all friction. The faster you drive, the air friction becomes more significant and a bigger waste of energy.  Let's take a hint from airplanes in the sky and streamline our cars.  

A pickup truck is a great vehicle to convert to electric simply because it can safely carry a lot of heavy batteries. A pickup truck is not a very aerodynamic vehicle though. 

I have been reading about a guy named Phil Knox who for the past 38 years has modified the aerodynamics of his vehicles, increasing the fuel efficiency. 

This guy was way ahead of his time.  

I want to try some of the aeromods that he did.  Notice the hood fairing, and the wheel fairings.  

Nice aerodynamic bed cover!  

If Phil can do this to an old '62 Dodge D-100 pickup, why can't I do it to my '92 Toyota truck?

Another fellow AndrewJ has also followed Phil's legacy and has aeromodded his '94 Honda Civic.  He now gets over 55mpg.  

Improving the aerodynamics is especially beneficial in an electric car.  Not only does improved aerodynamics reduce the amount of electricity needed for a given commute, it also extends the driving range of the vehicle too. 

I must try this too!

Grill Block:  I started out with a piece of sheet metal on the front of the truck that blocks off the grill.  This keeps air from entering the engine compartment creating air turbulence.  This simple piece of metal reduces drag and in turn, reduces the current draw of the motor by almost 6 amps while cruising at 55mph.  

Well that was easy, what else can I do to improve things?  

Air Dam:  I made an air dam out of a $34 sheet of 4x8 plastic from Home Depot. It is fairly sturdy stuff and meant for shower walls or other waterproof applications. It's bumpy on one side, perfectly smooth on the other and the same color of white as my truck. “Perfect! No painting required.”

An air dam is a quick fix that prevents air from entering the aerodynamically dirty areas under the vehicle, reducing the drag.   While an air dam increases the frontal surface area, it actually increases the overall fuel efficiency of the vehicle.  

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