Bolt-On Cool

Heat is the enemy of power. You know that, right? Heat robs density from an engine’s incoming air, diluting the impact of combustion, which ultimately costs horsepower. Heat is bad, mmmkay? To make power, you want air, lots and lots of cool dense air, mixed with a healthy swig of high-quality fuel. Unfortunately, one of the prime means of packing more air into an engine—turbocharging—also creates a tremendous amount of heat in the incoming air charge, stealing away some of the turbo’s pressurizing benefits.

That’s where intercoolers come in. Plumbing an intercooler into the air tract between the turbo compressor and the throttle puts a radiator in the air stream, enabling the hot air leaving the turbo to chill before it reaches the engine. As the air cools, it becomes denser; more of it can then fill the combustion chambers prior to ignition.

Now, if you’ve turned up the wick on a stock turbo system, you may find that the car’s original-equipment intercooler (if it even has one) can’t cope with the increased temperatures coming from the turbo’s higher boost levels. In that case, an intercooler upgrade is in order, although its installation is not always an easy task. Some intercooler kits require you to relocate underhood components and sort out complex plumbing issues. At the end of the day, you might wind up with an intercooler that just sits in the engine compartment and soaks up the surrounding heat. Not good.

ABD Racing is introducing a front-mount intercooler kit for Mk IV Golf/Jetta cars that’s nothing like the nightmare described above. For one thing, the intercooler mounts under the front bumper, so it’s in the air stream and away from the hot engine bay. To cool the charge even further, the pipe that returns air to the engine also sits in the air stream flowing under the car. To simplify the installation, ABD has figured out how to plumb its intercooler directly into the pipes that feed the OE intercooler. The only component that needs any relocating is the stock ’cooler, which becomes a fancy doorstop or paperweight.

If you’re like us, you cringe a bit when you hear the term “bolt-on,” because bolt-on kits are never really as simple as they’re made out to be. They all need a little welding here, a little fabrication there, and usually a big whack or two from a hammer. Not in this case. ABD Racing’s intercooler kit does require drilling a couple of holes and a bit of plastic trim cutting, but otherwise this is as close to a legitimate bolt-on kit as we’ve seen. The toughest part of this job may be removing the front bumper cap. Once it’s off, the job will take an hour—maybe two if the fridge in the garage is freshly stocked.

As you read through this installation, keep in mind that the kit we photographed was a prototype. Those of you with good eyes will notice rough welds on some of the pipes; they will be smoothed out for production. ABD Racing was still sorting out some of the details when we visited the shop, but by the time you read this, the ’cooler kit will be available for sale.

One of the details still unsolved was whether or not the intercooler will fit behind a stock Golf or Jetta front bumper. For most of the people interested in this upgrade, though, that probably won’t be an issue. ABD’s Adrian Saldivar, who spun the wrenches for our camera, figures “people who will want this intercooler will have already made some mods to their cars. The first $1,000 they spend won’t be here; it’ll be on a chip, a new turbo, an intake, stuff like that. They’ll be pretty serious.” So the ’02 Jetta wagon used to illustrate the installation will probably be typical of cars receiving ABD’s kit. Despite its just-off-the-showroom-floor status, it had already been modified with a Split Second Turbo Boost controller (pushing about 14 psi), TurboXS bypass valve, ABD Quick Flow intake, Techtonics down pipe, high-flow cat, and Supersprint after-cat exhaust system.