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S550 How to Install Trackspec Motorsports Fender Vents

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Just installed these to match the GT4 hood vents on my GT350, but install should be more or less identical on a GT or GT500.

Tools used:
Trim pin removal tool
Dremel
Dremel cutoff wheel
Dremel sanding wheel
Drill
1/8" drill bit
Cleco tool and 7 cleco pins
Satin/matte black spray paint
Masking tape
Marker
Pop rivet tool
Floor Jack
Jack Stands
Torque Wrench


The kit includes a template for both passenger and driver's side. First remove the pre-scribed areas on the template so we can use this to mark where we'll be cutting our hole. Cover the fender area in masking tape and align the templates onto the fender. I located the top of the template about 2" below the fender/hood gap and the rear most hole on the template was about 19-1/4". Hold this tight with some masking tape.

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Trace an outline with the marker on the outside of the template and through the inner openings.

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Jack the vehicle up now, remove the wheel and tire and remove the inner plastic fender liner by removing all of the push pins. Also remove the fender liner insert at the top of the fender.

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Cover some additional area with masking tape to protect the paint. Now take a deep breath, drill 1/8" holes into the 4 corners and then use a Dremel with a cutoff wheel to make your opening. Once the opening is cut, switch to your sanding wheel and smooth out the edges so you don't slit your own wrists on the exposed metal edge. The fender is aluminum on the GT350 so corrosion isn't a massive concern, but take some black spray paint and paint the inner fender with some matte/satin black paint as it will be visible through the vents.

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Align your fender vent within the opening by aligning the front upper corner and the upper top edge. Drill the upper front hole with the 1/8" bit and insert your first cleco pin. (I bought the tool with 10 pins for like $20 on Amazon and worth the price). Keeping the top line aligned, press the lower corner furthest from the first hole you drilled and drill out another hole and cleco that hole in place holding down the two furthest sections. Now work around in a clockwise motion from the upper left to maintain alignment correctly.

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Now trace the outer perimeter of the vent with the marker again and remove the clecos. You'll want to now take a razor blade and score the tape between the holes you just drilled. This is done because the notches in the vent will expose the color underneath and the cut opening in places and we want to mask this. Your cuts don't have to be perfect as the vent will cover up any wavy lines (like mine)

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Re-insert the vent with the cleco pins and work from the inside out. Do the "center" holes first. Then move to the lower front hole, then the upper rear hole. Next to last will be the lower rear hole, and finally the front upper hole.

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Now that the vent is secured it's time to open up the fender liner so that it's functional. I used a step bit and drilled 1" holes across the upper outer section of the fender liner. Since I have a GT350 I also opened up the factory openings for the factory fender vents as well.

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Clean up all the edges and then reinsert the inner fender liner and admire your work.

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Why retain the front/upper portion of the fender liner at all?
The front portion is utilized on the GT350 to help align the factory brake ducts to the wheel well opening. The vents (centered on this picture) are held on by one plastic push pin to the front bumper behind the center vent and with 2 push pins and a pass through hole on the fender liner.
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It was also my belief (and without a wind tunnel, most aero work is educated guesses) that the fender liner provided a smoother air flow pattern for the air trapped in the wheel well. By utilizing the holes in the specific locations I made them I was hoping to direct the air to the opening I'd just created at the top/middle of the fender and to the lower to mid rear of the fender.

I purposely left the liner un-touched in the area near where the paper towels are sitting in this photo in order to try and discourage air from going up and getting trapped in the upper rear portion of the fender that isn't currently vented.
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Note the large area above the factory vent and GT350 badge I didn't necessarily want airflow going into.

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