It is no mystery the factory-tuned 1.8T is restricted in many ways. Throughout the VW/Audi aftermarket industry, tuners and enthusiasts have upgraded the 1.8 motor to perform well above its original output. Components such as the exhaust, intercooler, air induction pipe and software have shown good gains when uprated. The performance limitations of the stock parts can somewhat be attributed to manufacturer regulations, vehicle emissions and cost.
Our Project Silverstone was already equipped with several performance upgrades to boost its performance. It's been flashed with GIAC software and has an Evolution Racewerks front-mount intercooler (et 9/06), Samco Sport air induction hose, Techtonics Tuning exhaust with downpipe, Forge Motorsport diverter valve and Evolution Sports BMC intake.
While these parts comprise the most popular bolt-on products a 1.8T owner can install, a bigger turbo would be the next major step to gain considerably power, but unfortunately it carries the heaviest damage to our checkbook. Consequently, it's something we've not got round to. However, there's something else we overlooked - the exhaust manifold.
Notice how much bigger the...
Notice how much bigger the Kinetic manifold is compared to OE.
Quick ReviewA turbocharger is a pump that compresses air into a small space. Turbochargers are highly efficient because they use spent exhaust gases to power the pump. The exhaust gases represent two strong forms of kinetic energy: heat and pressure. The additional energy from the gases is routed from the exhaust manifold and then forced into the turbocharger. Because the exhaust manifold has to transfer energy to the turbo to create horsepower, it's an integral part of the overall performance.
Kinetic ManifoldKinetic Motorsport recently released a new turbo exhaust manifold for the 1.8T. The manifold is designed to replace the factory manifold on Mk4s and Audi TTs. The unit is custom-cast and designed to provide increased exhaust flow.
With all the modifications on our GTI, the factory manifold had become a bottleneck because it wasn't engineered to handle more boost and horsepower. The original manifold flows sufficient for a stock car and is designed for easier removal by technicians.
Kinetic tested its new turbo manifold on a Mk4 1.8T equipped with a K04 turbo upgrade. The company states its new manifold doesn't substantially increase peak power, but is designed to boost overall power across the powerband. "The first engine upgrades for a 1.8T are chip and exhaust," explained Shawn van Neer of Kinetic. "After these changes, the next big thing is a good turbo manifold. The great thing about our manifold is that it works in every stage of your build. It offers you more power the further you go. It'll continue to reward you. If your motor is completely built, a new turbo manifold will make a huge difference, but it'll also help if you just have a stock turbo and a chip."
 DRS technician begins removal...  DRS technician begins removal of the front axle. |  The exhaust manifold is located...  The exhaust manifold is located behind the motor so it's difficult see what you're doing. |  DRS preparing to install the...  DRS preparing to install the new manifold |
 With clearance for the Kinetic...  With clearance for the Kinetic manifold at a premium it becomes difficult to bolt it to the turbo. |  DRS technicians monitoring...  DRS technicians monitoring the ECU for problems. |  |
Step By StepInstallationStep 1. It's important to let the car cool down completely before starting the project because the exhaust manifold is one of the hottest parts of the engine. It can take over an hour before it's safe to work on it.
Step 2. Working with the car on a lift makes the installation easier because you have to remove parts under the hood and from under the car. To gain access to the turbo and the manifold, first detach all the obstructing parts. For our GTI this included the strut bar, followed by the intercooler piping, air induction pipe and heat deflector
Step 3. The next major step to reaching the turbo is removing the passenger-side axle. Removing the axle begins by unbolting the wheel, undoing the axle nut with a 30mm 12-point socket and finally, unfastening the six 13mm bolts securing the axle to the car.
Step 4. We now have access to the turbo and the exhaust manifold. Using a 17mm socket, undo the three bolts that secure the manifold to the turbo. Next, disconnect the bracket support for the turbocharger.
Step 5. Now remove the 13 nuts and washers fastening the manifold to the cylinder head. Use lubricant and a 12mm socket wrench to remove the final pieces of the manifold. There are two nuts that require the turbo to be lowered an inch in order to access them. Once all nuts and washers are removed, the manifold and exhaust gasket should come away. It's vital to cover the exhaust and turbo openings to ensure no foreign objects accidentally drop in.
Step 6. To install the Kinetic manifold, re-use the washers from the factory unit. The Kinetic kit comes with new nuts, bolts and exhaust gasket to install the new manifold. Kinetic also provides additional gaskets for a more secure turbo-to-manifold fit. For our GTI, DRS began by setting the Kinetic gasket and the bolt closest to the manifold runners before situating the manifold in place - because the new manifold is bulkier, it would be impossible to slide that particular bolt in otherwise. From there, DRS installed all three bolts at 22 lb/ft torque along with the nuts and washers fastening the manifold to the head, which is the most time-consuming part of the installation. We re-used all the factory washers except one because there was less room for it to fit. The lack of room also restricted us from torquing the nuts to vehicle spec. DRS recommends using a 0.25" ratchet because it offers the ability to tightly secure without over-torquing. Another recommendation was to tighten the nuts in diagonal sequence.
Step 7. Once the new manifold is secured, reinstall the detached parts in reverse order. As a final note, the DRS technicians mentioned that Kinetic's manifold was nicely constructed. All the dimensions lined up correctly with the head and turbo for a fast and simple installation that took a total of four hours.
Dyno TestingThe DRS facility housed a built-in two-wheel drive Dynojet dynamometer in the shop. The factory manifold was measured three days before the Kinetic manifold results. The same tank of fuel was maintained to ensure consistent ignition. Both tests were conducted after the vehicle had cooled down properly. Unfortunately, one variable remained out of our control - ambient temperature. The temperature on the final day of testing was 5-10 warmer than the initial test.
The GTI also suffered intermittent misfires from a prior dilemma. DRS were the ones to diagnose the problem and identified spark plugs as the culprit. After a quick swap, the car was running smoothly and we were able to see consistent gains with the Kinetic exhaust manifold.
After driving the car with the new part, it feels more powerful than the dyno numbers alleged. Although it only showed a gain of 3whp and 5 lb/ft, the improved torque could be felt instantaneously once the turbo reached boost. Even after the initial gain in torque, we noticed an increase in power to redline. The car accelerates harder and feels less restrictive. We might now be at the maximum output for the factory turbo, so stay tuned for more upgrades since we feel this manifold has more to offer with a bigger turbo.
Dynamic Racing SolutionsGoing into its fifth year of business, Dynamic Racing Solutions (DRS) has expanded its services beyond maintenance, performance upgrades and engine swaps for VW/Audis to include professional race support, engine management solutions and fully-built project cars. In 2005/06, DRS assisted Race Prep Motorsport - a Porsche 996 Grand Am Cup team - as well as Rockwall Honda - a Super GP motorcycle team.
With several years of diverse racing and service experience behind them, we knew we could trust Project Silverstone to the DRS technicians at its facility in La Habra, CA.www.racesolutions.com, 562/694-2226