Welcome! This is my 2005 Chevy Colorado Cold Air Intake Mod. For low
bucks, you can help your truck breathe and perform a little better than stock! Firstly the "science" behind a cold air intake is fairly self-explanatory. You are drawing "Cold" air as opposed to "Hot" air into your engine. Cold air contains more oxygen and creates a more complete burn in the engine, this will increase the performance of your vehicle. Secondly an unrestricted intake makes it easier for the motor to draw more air in and rev up easier. You can buy an intake for 100-300$ or if you are like me you welcome the challenge of building one yourself.

This is my first Instructable, feel free to message me with helpful advice. Full credit goes to "bassboarder85" on the "ColoradoFans" forum, I got the idea from him, I just wanted to share his idea.

Keep in mind that a Cold Air Intake might fail an emissions or visual inspection. Be sure to check before you begin installation. Where I live we do not have emissions tests, so break out the drinks and lets get started!

Step 1: "Cold Air Intake" Myths

This is not necessary to the installation however there are some points to keep in mind.

There are lots of myths running around concerning "Cold Air Intakes". Some aftermarket companies claim radical amounts of horsepower gains all the way to 25+hp!!! At the other end of the spectrum there are people who say a cold air intake will make you lose power. I will do my best to address them both. The entire point of this mod is hunting colder air at a faster rate.. "Are you actually drawing in cold air?" Lots of aftermarket intakes end up sucking hot air into your motor which defeats the purpose.

So if you can increase performance by a cold air intake, why don't they come stock?? I'm glad you asked.
The OEM intake assembly is bound by some rules by the manufacturer, to name a few.

Emissions: The motor has to be emissions compliant. More intake means more exhaust, which affects emissions standards.
Noise: Another concern by the manufacturer, the OEM intake acts as a muffler to quiet down the motor. Some of us don't mind a louder vehicle however there are decibel limits the manufacturer is bound by.
Price: Materials, research and development, labor and installation.
Reliability: It has to work and perform in almost all climates, regardless of altitude or temperature.
Performance: The intake has to help the motor perform at its absolute best with all of the hindrances mentioned above.

These are but a few of the hurdles the manufacturer has to deal with.They must balance all of these in order to have a good all-round vehicle. But what if we were to take out Noise as a concern? What about price? Emissions?The scales would tip potentially boosting performance.

Step 2: Gathering Materials/Tools

For this Instructable we will be using electrical conduit for the resonator delete, however we will be retaining the OEM air-box. We will be connecting the appropriate hoses to avoid and check-engine lights. Below is the materials list from "Bassboarder85" on the "ColoradoFans" forum. Full credit to "Bassboarder85".

#4 Clamp 2 pk

#8 Clamp 2 pk

3 inch (schedule 40) 45 deg Elbow

1/4" ID Hose (rubber) 2 ft

1/2" ID Hose (rubber) 2 ft

1/2" Brass Hose barb

1/4" Brass Hose barb

3" Flexible couple 2x

Tools

Screwdriver(flat)
10+12mm socket with extension
File
Drill-bits with power drill
Hacksaw or chop-saw

Step 3: OEM Intake Disassembly

Out with the OEM, in with the new. This disassembly is for a 05 Colorado 5 cylinder. These instructions may work for similar year models. Anyone can do this however if you don't feel up to it, try to find a mechanically inclined friend to help. Do not get anything inside the motor. Try to keep a clean work area, if the intake is dirty wipe it down with a damp cloth before starting.

Disconnect intake resonator hoses(should be a 1/2 inch breather behind the resonator and a 1/4 inch up front)
Loosen all four hose clamps
There are two 10mm bolts holding the resonator to the valve cover, remove both
You should be able to slide both clamps off the resonator and pull the box free
remove the flexible couplings

Step 4: Building/fitting the New Intake

Slide the 3 inch couple over the engine side of the intake. The second 3 inch couple goes on the air filter side however there is a little raised notch preventing it from fully seating in place. Use a file to sand down the notch for a good seal. If your 3 inch couple does not quite fit over the filter side, you can file the inside of the couple for ease of installation.

The 3 inch 45 bend is going to be too long for this application, even though it should be partially inside of each couple. You have to cut it down to size, so it can slide in between the 3 inch couples. Be sure to clean the inside of the pipe to prevent shavings getting inside the motor. Test fit the pipe often.

After this you will have to mark for the fittings. These fittings will have rubber hoses going to their respective systems. This is so your vehicles computer, can still get all of the necessary data for optimum performance.

You will have a 1/2 inch fitting going on the backside of the pipe, and a 1/4 on the front side of the pipe. Its not too terribly complicated however its hard to explain in words. (Use the pictures to avoid confusion)

Do not drill holes while pipe is installed, plastic shavings will get into the motor and cause problems.

Step 5: Finishing the Intake!

When you have the holes marked for the fittings, remove the pipe from the engine and drill the holes so the fittings are able to spin freely inside without being oversized. JB Weld the fittings in place to avoid air leaking. Allow the JB Weld to cure before continuing.

Once the JB weld has had a chance to cure ,install the pipe for the last time. From this point you can cut the 1/2 inch and 1/4 inch rubber hoses to size. Be sure to install hose clamps on both sides of the 1/2 and 1/4 inch for a good seal. Go ahead and give everything a once over before initial test.

Your finished!!!! Take your vehicle for a test run and let me know what you think! I have had mine for a long time and no complaints whatsoever. In the future I would like to wrap it in heat-reflective tape in hopes of further increasing gains. I would also recommend you install a higher flowing air filter to make better use of your new intake, however this is simply preference and is not required. Please post a picture if you did the Instructable or if you did something similar. I want to inspire others because I am inspired by your success!