Ford f150 dedicated CNG - Fuel Economy, Hypermiling, EcoModding News and Forum

bagmister · 03-11-2015, 12:20 AM

Greetings!,
so i have a ford F-150 dedicated CNG. i average about 17 to 19.5 mpg it's a 2 door long bed (8 foot roughly) = 98" long. 72" wide cab stands about 22" tall from top of bed line. if i were to draw an imaginary line to the top of the cab to the top of the tailgate at a straight line it would be 106" long. I was looking into making an aero cap. I want to build it from scratch so i decided to go with wood seeing as that is what's cheaper and i have access to it. But i have no idea how to add a 3rd brake light to it. What would be the most efficient angle? can i do a straight back drop?(tear Drop?) maybe an arch?
I'm thinking of doing a cap similar to the red 06 canyon i saw on these forums. I've been poking around for some time just decided to start. i haven't measured the angel that the truck cab is tapered to. but the top of the cab is 50" roughly.
What do you guys think? I would like to have this done by April. I will be driving down to Las vegas from where i live near salt lake city. a very good chance to test experiments. But also out of necessity. There are stretches were the next CNG station might be to far... hence I need to get more mpg out of the truck. I have noticed the engine likes to cruise around 55-60
for those interested.
the body is the 1997-2003 body style
Engine is 5.4 2 valve modular/Triton engine from ford.
I'm building a cost chart and i think I'm going to be spending around 3-400.
any suggestions would be welcomed.(I'm new to this)

Baltothewolf · 03-11-2015, 02:11 AM

Wow that's pretty cool, did you just convert it from gas to CNG? What mods were required to convert it (if any).

About the bed, there is a guy here that did his truck, you want to go with a tear-drop kinda style. Gains should be in the 3-4mpg range I believe.

Baltothewolf · 03-11-2015, 02:12 AM

Wow that's pretty cool, did you just convert it from gas to CNG? What mods were required to convert it (if any).

About the bed, there is a guy here that did his truck, you want to go with a tear-drop kinda style. Gains should be in the 3-4mpg range I believe.

bagmister · 03-11-2015, 03:12 AM

It came dedicated from the factory. No modification was needed

I'll do a tear drop then. I need to design the sides and latch. Were would one be able to find the gas or hydrolic shocks? To hold the lid up when open? How do you secure it to the bed? My tail Gate doesn't have a lock on it. So if possible I'd like to cover the latch area when it's closed.

JRMichler · 03-11-2015, 02:09 PM

My topper is held open with the same gas struts as used to hold hatchbacks open. NAPA has a complete selection. If you ask the person behind the counter, they have a catalog that lists all the sizes and forces.

I bolted it to the truck box. Two bolts on each side, and two more across the front.

The opening latch handle is from a garage door. Close the lid, then turn the handle to latch. It's lockable. If I wanted it lock the tailgate, I would extend the rear piece down just enough to prevent the tailgate from opening when the lid was latched.

bagmister · 03-11-2015, 04:23 PM

Thanks for responding JRMichler. Your top is the style I like. I looked at your profile pictures of the build process. Thanks for answering most of my questions. I do have one more though. How did you add the 3rd brake light? I'm unsure how to go about this.

JRMichler · 03-11-2015, 09:42 PM

I found an LED brake light in the auto section of Walmart. Then I ran a pair of wires to the hot side of one of the rear brake lights and ground.

I ran four wires into the topper. Ground, brake light, 12 volt straight from the battery, and 12 volt switched (on when the ignition is on). I put a four prong SAE connector in the box so I can unplug the topper if I ever take it off. The SAE connector is the flat connector used to connect trailer wiring. Any auto supply store has them.