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Fuel Efficiency Upgrade: Headers, Exhaust, Throttle Body, Aerodynamics A Ford F-150 gets several upgrades, all leading to better efficiency and higher mpg. From "Weekend Mechanic" episode WKM-405

Bruce Bonebrake installs a tonneau cover on a 2004 Ford F-150. It's just one in a series of projects aimed at improving the truck's fuel economy.

In this project, Weekend Mechanic host Bruce Bonebrake shows how to improve fuel economy--actually with several projects--on a 2004 F-150 Ford pick-up truck. The efficiency-boosting enhancements include new exhaust headers, new cold air intake system and throttle body spacer to improve air flow and fuel atomization. Together these modifications result in a more complete combustion, more efficiently burning engine--and fuel economy increased by about 4 miles per gallon.

He also installs a performance muffler and exhaust system, with larger and better-designed pipes than the stock exhaust system. This improves the handling of exhaust gasses, increases horsepower and torque and ultimately leads to greater fuel efficiency.

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Bruce installs a cold-air intake and performance air filter to help enhance fuel efficiency.

Next, a retractable truck-bed tonneau cover is installed to reduce drag and wind resistance, also improving fuel economy.

Finally, the vehicle's on-board computer is re-flashed using a flash tuner system. Combined, the improvements add up to real fuel savings in the form of about a 10 mpg increase.

Tools and materials:

In addition to standard auto-mechanic's tools (wrenches, ratchets, extenders, screwdrivers, nut-drivers, torque wrench, etc.), some of the specialty tools that will be needed for this project include:

combination wrenches
pliers
screwdrivers
socket sets

Safety Alert: Always wear eye protection and ear protection, and follow proper safety precautions, when working with power tools. Also wear eye protection any time that you are working beneath a vehicle.

Safety Alert: As a standard safety precaution, always disconnect the vehicle's negative battery cable before you begin work on any electrical or mechanical components.

Safety Alert: As a standard safety precaution, don't rely solely on a jack to support the weight of a vehicle. When using a jack to access or work beneath a vehicle, always use jack stands for support. Make sure that the jack and stands that you use are rated for the weight and type of your vehicle.

Upgrades summary:

• exhaust headers, cold air intake system and a throttle-body spacer
  
• performance exhaust system
  
• retractable tonneau cover
  
• re-flash the vehicle's on-board computer

	The new performance header

Intake and Exhaust Upgrade Overview

We begin our upgrades by removing the stock exhaust system and installing new headers, muffler and exhaust pipes.

For this project, we selected JBA's Cat4ward headers, which are a suitable upgrade for many of today's emissions vehicles. The headers are designed to deliver performance gains without compromising your vehicle's emissions-control equipment, increasing your vehicle's overall efficiency. The results include significant increase in horsepower and torque throughout the RPM range, improved throttle response and, in some cases, enhanced fuel economy. The kit includes the hardware for a relatively simple easy bolt-on installation.

The PowerAid throttle-body spacer serves to raise the throttle body by one inch. The additional height combined with the specialized Helix Bore creates enhanced airflow that improves fuel atomization, producing more complete fuel. This results in improved fuel economy and a boost to low-end torque.

Exhaust Headers, Cold-Air Intake System and Throttle-Body Spacer

The basic steps in the intake and exhaust-system enhancements, as shown in the episode, are listed below:

• First, remove the air duct and disconnect the mass air-flow (MAF) sensor.

• After removing the mounting bolts, the old air intake system comes out.

• Important: Be sure to disconnect the battery.
  

  Figure A

• With the truck raised up and the wheel removed, remove the inner fender to gain access to the exhaust manifolds (figure A).

• The exhaust manifold bolts aren't easy to reach and can be a little stubborn, but with a little perseverance, the old manifold can be removed.

• The high-heat gasket goes into place.

• Fit the new header in and onto the mounting studs.
  

• Install the bolt and washer to the rear top hole and the factory nuts onto the remaining studs.

• Tighten the fasteners down in an alternating sequence so the header flange doesn't bind.

• Check the fit of the new header.

• Important: On an installation of this type, always check for clearance from brake lines, wiring and other systems.
  
  
  

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  ALSO IN THIS EPISODE:
  	Fuel Efficiency Upgrade: Headers, Exhaust, Throttle Body, Aerodynamics