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Custom Air Intake: Remove Factory Air-Box and Build Intake System Mitsubishi Eclipse--Engine Upgrade, Part 1 of 3 From "Tricked Out" episode DTRK-305

(Continued from page 1)

Tools and components used in the intake modification

Cold Air Intake: Why Bother?

Typically, 40 percent of the engine's combustion energy is lost as heat energy through the exhaust, 30 percent is used to keep things cool under the hood, and 5 percent is lost through friction and parasitic drags like the power it takes to pump air, fuel, and exhaust in and out of the combustion chamber. The good news is that there are some easy things you can do to combat those losses, for increased power and better fuel economy.

We start this project by making it easier for the Eclipse engine to draw intake air by removing the restrictive factory intake air-box and replacing it with a custom cold-air intake system. The first step is to remove the factory setup.

Materials and tools needed for the first phase of the project:

standard shop tools
marker
utility knife
safety glasses
hose clamps
hacksaw
drill and drill bits

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	Figure A
	Figure B

Removing the Factory Air-Box

• Remove the old factory setup. Start by disconnecting the negative terminal of the car's battery.

  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.

• Loosen the band clamp holding the intake pipe to the throttle body, and then slide back the hose clamp at the engine side of the crank-case ventilation hose and pull both of the hoses off the engine.

• Next, pop loose the four spring-clips that lock down the air box lid and remove it along with the intake pipe assembly and the air filter (figure A).

• Remove the three 10mm bolts securing the lower half of the air box to the fuse box tray (figure B).

• The inflow tube is released next by pushing two of the four tabs down, and then the box can be removed from the car.
  

  Figure C

Next, it's time to build the custom short-RAM intake system. Begin by constructing a short-RAM pipe. The new system is going to go into the same place as the old restrictive box, so it needs to make a 90-degree bend off the throttle body, then a big straight pipe down to the front, and a 45-degree bend to position the filter correctly. The best way to do it is start at the throttle body and drop in one piece at a time until the entire pipe system is complete.

When the pipe is ready take it to the car and add it to the coupling (figures F and G).

Figure F

Figure G

Figure H