The introduction of the Z06 Corvette for the 2001 model year brought with it many improvements over the existing “base” C5; foremost among them was the LS6 engine, initially rated at 385, and later 405 horsepower. Other upgrades included wider wheels and tires, a revised suspension setup, and of course functional rear brake cooling ducts. Those ducts would prove to be a popular upgrade for C5 owners as the years passed, sometimes functional, sometimes merely for looks.
In our case, when we recently rebuilt Project Y2k’s transmission and differential with assistance from RPM and LG Motorsports, we found another use for these versatile factory ducts. You see, the transmission and differential coolers included in the LG kit have heat exchangers that are designed to mount inside the rear inner fenders ahead of the wheels, with the trans radiator on one side and the diff radiator on the other. The only problem was that on our 2000 Corvette coupe, that space had no airflow, being completely enclosed.
Gotta let these puppies breathe!
The simple solution, of course, was to order up a set of Z06 ducts from our friends at Corvette Central. The four-piece kit (PN 335036) includes scoops and ducts for both the right and left side of the car. These OEM parts (which are also available a la carte if you’re just interested in doing a cosmetic swap) are a pretty easy install, as long as you have the courage to cut into your Corvette.
Corvette Central is a one-stop shop for all kinds of performance and restoration parts for every generation of Corvette – we’ve previously done the Stage 1-4 power upgrades from Corvette Central Performance on Project Y2k, with terrific results. With this latest bit of work, we’re dipping into their vast warehouse of GM and aftermarket exterior components.
Looking a bit like postmodern art, the kit includes factory GM left and right scoops and ducts.
Just Do It
There’s not too much more to be said about the parts themselves, so we’ll just jump straight into the installation. The first step is taping together and cutting out the templates – they will allow you to accurately cut the rocker sills on your Corvette in the right places for the scoops.
Never has ‘measure twice, cut once’ been more important! The template has registration marks to help you get it accurately positioned on the rocker panel before you mark the position for your holes.
After triple-checking the position of the template, it was time to mark the outline of the hole with a pen, and locate the drill points with a center punch.
No turning back now… Drilling the holes for the mounting studs that will pass through the body and hold the scoops in place. By using the center punch to mark the hole locations, you ensure that the drill bit won’t “walk” and scratch up something it shouldn’t
After drilling starter holes in the tight corners, we used a body saw to start cutting… We intentionally started off undersize, because you can always cut more, but the opposite isn’t true.
With the hole rough-cut, you can finally see the cooler peeking out. Note how dusty this process is.
Here, you can see how the brake duct snakes around the inner fenderwell to deliver cool air to the brake discs. In our case, we won’t be using them since we are utilizing the scoops to cool our fluids instead of the brakes, but it gives you an idea of how the factory parts lay out.
The brake ducts, being factory parts, bolt up to factory holes, should you choose to use them.
Because of where the radiators sit, we had to modify the inner portion of the scoops a bit with the trusty body saw. The good part is that we were able to make the duct tightly conform to the face of the cooler, improving airflow.
Erring on the side of caution, we cut the holes undersized, then trial-fitted the scoops, enlarging the opening as we went using a flap wheel. This ensured the closest possible fit.
Nuts threaded onto the backside of the studs secure the scoops in place, and this part of the job is complete.
Of course, if the air has no place to go after it’s passed through the coolers, there won’t be any flow, so we drilled relief holes in the inner fender liner to allow it to exit.
To keep road crud kicked up by the tires out of the fenderwells, we covered the holes with an aluminum soffit vent grille, sourced from Home Depot and painted matte black. Pop riveted to the fender liner, we were ready to button it all back up.
The finished product – functional and good looking!
So, thanks to our friends at Corvette Central, our transmission and differential coolers are now completely functional, and we’ve added a bit of Z06 flair to our Corvette coupe. The installation can be done in an afternoon with basic tools – if you don’t have access to a body saw, thanks to the nature of the sheet molding compound used in the Corvette’s body construction, a variety of different tools will work, including spiral drywall saws and jigsaws.
If you’re nervous about the precision of your cut, do what we did – start undersized and sand or file to the right dimensions. Also, keep in mind that because of the wide “lip” around the edge of the scoops, even an oversized cutout won’t be visible once you’re done, provided you don’t hack away with reckless abandon.
All in all, it’s a job that any DIY’er can accomplish for themselves – we highly recommend it! Now, we’re going to have to dig into the online catalog at Corvette Central to look for more practical upgrades like this for our project car…