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490 Posts
Discussion Starter · #1 · (Edited)
I teased everyone long enough about posting up this DIY and now here it is finally.

Tools needed:

Tin snips/metal shears
power drill
flat head screw driver/maybe phillips too
4 1/4" metal hole saw
Socket set
Measuring tape
2 clamps
Work bench or nice solid surface you don't care too much about
Metal drill bit and 2 matching bolts

Materials needed:

one 24" x 24" aluminum sheet metal (minimum size). .063 gauge aka 1/16" thick.
I used a 36" x 36" sheet to have enough to do 2 just in case... and I needed it
Engine enamel
Weather stripping
Heat resistant silicone sealant or similar glue
Large piece of cardboard
4" Intake tub (metal elbow) found at most hardware or parts stores
K%N filter with 4"hole
Rubber coupler
2 vice clamps that will fit 4 inch diameters.

To make this easier on you I will give you all the measurements you will need so all you have to do is draw it and cut it.

Remove the stock air box using this video. NOTE YOU DO NOT HAVE TO REMOVE THE FRONT SNORKEL PART!

Using the pictures below, measure out and draw the template as seen on a piece of cardboard. Each line on the right is spaced 1 inch apart

When done it should look like this

Now at the bottom I made a few changes so ignore that part. you will see that I wrote keep tab. That piece should go all the way to the solid line to the right and the tab should also extend down 4 inches as I show here in red. Since I already cut my shield I just cut a plate and glued it in place as you will see.

When done use the back end of the sharpie to score the cardboard along the dotted lines and then make the bends so that your template looks like this

The bend by the hole is 90 degrees, the bend after that is also 90 degrees, the last bend ends up being more of a curve. Test fit your template on your car and you will see where adjustments need to be made.

Now once you have drawn out and cut the template, lay it on your sheet of aluminum and trace it. Before you remove the cardboard, lift it slightly to make marks at the top and bottom for where your bends will be then draw dotted lines as seen here.

Now take your tin snips and cut out the shape of the shield. Wear gloves while doing this because the edges will be very sharp. Once you have cut out the outline, be sure to cut the slit as shown in the template pictures. keep the little tab on there, it comes in hand later.

Next Using the measurements I post mark the top and side edge for the hole cut out. Measure from the top of the shield and from the line that will be the 90 degree bend. Take your hole saw and line it up with those two marks and start drilling. Be sure to clamp the sheet down or have a friend hold it still. Also be sure the surface below is something you don't mind drilling into.

Now with the hole cut its time to start shaping. ***Quick Tip*** I traced the lines from the front of my metal to the back so I would know where to bend from both sides

Line up your marks with the edge of the work bench and from the center slowly push down on the side you want to bend. Run your hand up and down bending the sides to match the center. Next take your hammer and with medium force strike the metal along the bend to form a real tight edge. Spend some time doing this to get nice edges and make sure everything lines up correctly. When done your heat shield should look like this

Now test fit it. I found that I still needed to trim some more off the top. With the measurements I put on the template you have plenty of room to trim it down till its perfect. I think in the end I trimmed about 1/2 to 3/4 of an inch off the top to get it nice and flush.

Now at the front of the shield you want to clip the corner of otherwise it will cut into the sound deadening on your hood. I measure down 2 inches from the top then just cut a straight line angle. Nothing too fancy

Next get your self an L bracket. Test fit the heat and line up the L bracket with the bolt hole from the stock air box. Mark on the shield where the bracket meets up and mark the holes on the shield and drill them out (this will hold the arm of the shield in place once mounted).

Once you have finished your fitting and trimming its time to glue the bottom of the heat shield to the side. simply lay a thick bead of silicone or glue (I used black heat resistant silicone) between the two and let sit and dry. With the bending and shaping you did earlier, the two edges should already be touching before the glue, this just keeps them in a set place. Remember that little tab I mentioned earlier. tuck it under the 4 inch bottom part and glue it in place. this will help the shield keep its shape. Use a clamp to hold it there till dry.

Now clean the surface because its time to paint. You can use rubbing alcohol or paint thinner to remove any contaminants.

Spray several coats of primer (I chose black primer). At this point I also sprayed the intake tube to match.

Then several coats of engine enamel in whatever color you want, again I chose black
and this is the end result. At this time I sprayed the intake tube to match.

After its dry (usually over night or if you're impatient a few hours) run the weather stripping around the top, the side of the arm, the curve that meets the fender well and the bottom piece as shown here.

I originally did the front edge but then removed it because its its plast/rubber and was touching the expansion tank. I didn't want to take a chance of it melting.

Now just install everything. Slide the heat shield in place, bolt down the arm, mount the intake tube and rubber coupler to the MAF part of the engine intake and you are done. I still need to get an L bracket, I forgot to get one, but close enough for now.


579 Posts
err you going to remove the factory air duct? Looks out of place now. Nice DIY though.
He should of made an opening for the airduct...but awesome job though

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490 Posts
Discussion Starter · #12 ·

116 Posts
Def make a template as shown! A lot easier to get a great fit- here was mine- I changed the intake pipe to a 3" as well - turned out great! - made an AFE style air scoop as well - I have never felt the intake so cold in my life--- at highway speed it was at least 7-10 degrees cooler inside that box with the scoop than without--- Vehicle Engine Auto part Car Hood
Auto part Engine Vehicle Car Hood
Tire Bumper Automotive wheel system Automotive tire Automotive exterior
Auto part Engine Vehicle Automotive engine part Car
Auto part Engine Personal protective equipment Vehicle Automotive lighting

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