2004 Pontiac GTO Vortech Superchager Install - Back in Black Part III

Vortech's kit relies on boost...        read full caption Vortech's kit relies on boost from the V-2 SQ SC-trim supercharger unit to supply 2004 GTOs with a swift kick in the behind. The system retails for $5,686 in satin finish (P/N 4GJ218-010SQ) and $5,950 for polished (P/N 4GJ218-018SQ). It should be clear from the photo that there are a whole lot of components to the kit; but though time-consuming, installation is not beyond the abilities of the skilled backyard mechanic. (Photo courtesy of Vortech Engineering).

The first steps in the install...        read full caption The first steps in the install are to remove the entire air intake from the throttle body forward, and to remove the power steering reservoir from its bracket. This is done using the blade of a flathead screwdriver to bend a metal tab. No lines need to be disconnected as of yet, so the reservoir is simply allowed to hang loose for the moment.

The GTO engine covers must...        read full caption The GTO engine covers must be taken off permanently, as they simply can't be made to fit beneath the Vortech ducting and charge cooler box. Other companies utilizing either roots-style blowers or air-to-air intercoolers retain these covers; but anyone who would not buy a Vortech blower for such a cosmetic reason should probably not be reading GMHTP. The power steering bracket ahead of the driver's-side cover is then removed and will need to be modified shortly.

Thus far in our 2004 Pontiac GTO buildup, we had been adding a little performance here and there with some simple engine and chassis mods. These included: an air intake from LS1Speed; exhaust, sway bar bushings, and custom tuning from SLP Performance Parts; drag tires from Nitto Tire; and a skidplate, strut tower brace, and driveshaft loop from BMR Fabrication. (See the Jan. and Mar. '05 issues of GMHTP.) All of these items performed quite well and helped yield a well-handling, low-13-second street machine.

Pursuant to the old adage, "too much is never enough," we decided it was time to add some serious horsepower to our LS1-powered Goat-enough to blow the doors off of the Mustang Cobra, Chrysler 300C SRT-8, and 6.0L '05 GTO competition. Enter Vortech Engineering, one of the most trusted names in aftermarket supercharging systems.

Vortech's centrifugal supercharger kit for all 2004 (5.7-liter LS1) GTOs delivers 7-8psi of boost via it's quiet, proven V-2 compressor. This system is one of the cleanest as well; absolutely no accessory relocation is necessary, as the blower is driven off of a new pulley affixed to the power steering pump. Really, the only intrusions to the Pontiac's original underhood setup are slight adjustments of a few things like the power steering and coolant reservoirs. This is almost unheard of in the world of centrifugal supercharging.

In addition, Vortech uses air-to-water-to-air intercooling, or "aftercooling," to drop the temperature of the intake charge. This style of system does away with any added hassle of routing intake piping to a traditional front-mounted air-to-air intercooler. Instead, a mixture of water and antifreeze is pumped through a "charge cooler" box and then to the front of the car, where a heat exchanger cools the liquid via the rush of outside air coming through the grille.

Vortech claimed the kit would add 131 horses at the crank-a claim we would put to the ultimate test. To get baseline dyno numbers, we went to TT Performance Parts in Saddle Brook, New Jersey, specialists in LT1 and LS1 GMs. Strapped to TT's Dynojet 224x, our automatic-tranny GTO mustered 302.7 hp and 318.5 lb-ft. You may recall that this is significantly less than the 327 or so that we garnered previously in the buildup, and the reason is that we removed SLP's custom tuning prior to the latest test. This was to get a true appples-to-apples comparison of a stock-tune, naturally-aspirated GTO, versus a Vortech-tuned supercharged GTO so that the power increase seen with the blower wouldn't be confounded by extraneous variables. We're crossing our fingers to see upwards of 400 hp at the wheels post-installation.

Follow along in the photos as we begin the blower bolt-on on our Phantom Black test car. Next time, we'll finish the job by adding the blower ducting and aftercooler system. Then, we'll be about ready to get this show on the road and do some damage-to the competition and hopefully not to our drivetrain!

A few specialized tools are...        read full caption A few specialized tools are needed to complete the kit installation, and a GM power steering pulley puller is one of them. We bought a kit that fortunately fit in the space between the pulley and the radiator shroud. Had we unbolted the power steering pump so as to get a tool on there, removing the pulley would have been a near-impossible task due to the turning force needed to unseat it. We had to get creative and jam a hose clamp between the puller's sleeve and the clamping jaws to reduce clearance, so it apparently was not designed to work for such a small pulley.	Next the coolant reservoir...        read full caption Next the coolant reservoir must be popped off of its mounts. It will have to be relocated slightly to make room for the V-2 to sit in the engine bay, and Vortech supplies a series of spacers and a bracket to accomplish this, as well as additional hose and a hose mender to get the plumbing all connected again.	After removing the plastic...        read full caption After removing the plastic cover over the engine computer, the coolant reservoir brackets sitting below the master cylinder are removed. Vortech replaces both of these brackets with one of its own. Removal of the stock brackets, and reinstallation of the Vortech bracket, is eased greatly if one loosens the two bolts holding the computer to the fenderwell.
The computer heat shield needs...        read full caption The computer heat shield needs to be pulled out and the front corner trimmed to make space for the blower. This can easily be accomplished with some shears as this is not a metal part, and instead, seems to be made of some kind of pressboard. One must be careful when sliding this item in and out as it is very delicate.	This photo compares the Vortech...        read full caption This photo compares the Vortech coolant reservoir bracket (left) to the factory bracket (right). While similar in appearance, if you look closely you will realize they are mirror images of one another. The Vortech bracket reuses the stock rubber bumper and hardware; the hardware is removed using a star-shaped Torx wrench.	After modifying it with a...        read full caption After modifying it with a Dremel tool or similar instrument, the plastic computer cover is reinstalled. The notching is necessary to make room for the V-2, which will sit right in front of and on top of it. One should not worry about compromising dust or moisture protection because of this modification; after all, the F-body computers were lying in the engine compartment with no cover at all.
The plastic radiator cover...        read full caption The plastic radiator cover comes off next by unsecuring a few plastic fasteners. These 2-piece fasteners are easy to mangle so be careful with them, or you will have to look at a bunch of munched plastic pins tainting your otherwise-gorgeous engine compartment. We suggest using a tiny flat-blade screwdriver to gently pry the center of the pins upward, which will then allow the entire pin to lift out.	One part of the install that...        read full caption One part of the install that may surprise you is the need to remove the front bumper cover, as access in front of the radiator is necessary in order to install the aftercooler heat exchanger, water reservoir, water pump, and plumbing. Start by removing the three screws in front of each tire that secure the splash panels to the front fascia. Turning the wheels helps.	Aside from a few more screws...        read full caption Aside from a few more screws just in front of the hood latch assembly, the only thing holding the bumper cover on now are some rather irritating plastic snaps located on each side of the car below the headlight. The only way to unsnap them is a combination of a swift outward yank and a little prayer that none of them break (they are, you guessed it, plastic).
Since the intake manifold...        read full caption Since the intake manifold will now be under pressure, the valve cover breather can no longer be connected to the throttle body. After capping the port on the throttle body, a new hose can be run from the breather across to where the new supercharger air intake will be.	To make room for the charge...        read full caption To make room for the charge cooler, the passenger side coils need to be relocated slightly. To do this, one need only remove the bolts holding the black coil bracket to the aluminum valve cover. Many of the bolts look the same; be sure to remove only those bolts holding the bracket to the valve cover and not the ones holding the coils to the bracket.	With the coil bracket temporarily...        read full caption With the coil bracket temporarily hanging loose, the dipstick tube needs to be bent against the valve cover. Do this slowly and carefully, being sure not to kink the tube; it is a good idea to keep checking that the dipstick slides in and out while you bend. Once done, you probably will need two hands to carefully reinsert the dipstick, but it will go in. Also, the oil fill cap extension must be removed and the cap placed directly in the valve cover.