Tuning and modifying European cars was something that started out relatively similar to their Japanese counterparts, but over the last decade or so we’ve seen a shift in the way these big-name companies develop and market their products. Where Japanese car enthusiasts are usually left to mix and match parts along with home-brew tuning, a lot of European tuners create turn-key packages, which they sell in ‘stages’ for each corresponding bump in power.
The attributes of these packages are in line with the attitude and expectations that comes with owning a European car. The promise of high power that can be produced reliably is important; just as important as the convenience of installing such a simple, well-tailored kit. At the bottom end we see simple intake modifications and remaps, and as we progress we see exhaust system modifications and turbocharger swaps.
If anything, these packages are conservative by nature. In context, a Stage 3 kit (about as high as you can go without tearing apart your engine) for the turbo 2.0-litre found in the Golfs will net you between 280-320 horses at the wheels, depending on which tuning house you choose. That’s still within the realm of convenience, but the SR20DETs found in Nissan 180SXs or the 4G63Ts from the Mitsubishi Evolution series are capable of much more- without tearing apart the engine for strengthening.
Still though, these tuning houses are pushing the limits of these engines while ensuring that whatever they put to the market will still maintain those qualities of a European car in terms of daily driveability and refined performance. Integrated Engineering, an outfit based in the USA, has been working on something rather impressive for the last year or so: the IE450T kit for the Golf 6 R, which promises approximately 450 bhp on pump gas.
How does it do this? Well the largest piece of the puzzle is a Borg-Warner twin-scroll EFR turbocharger. These new-generation turbochargers are designed for a very wide range of performance, which comes with the twin-scroll design. We’ve yet to see twin-scroll turbos on stock Volkswagens, but they have been employed by BMW in their TwinPowerTurbo engines to great effect. Larger in size than the stock K04 turbo, this Borg-Warner unit can flow enough air to produce 450 hp without choking at the top end. The benefit of the twin-scroll design is that lag is heavily minimized, allowing for near OEM levels of turbo response.
To function with a split turbocharger inlet, a proper split exhaust manifold is necessary. The stock Volkswagen turbocharger manifolds are good for optimizing exhaust pulses so that there is little interference, but a proper split manifold has split outputs for each pair of cylinders, providing two separate exhaust streams for the turbocharger. Carefully developed and CAD designed, Integrated Engineering has put a lot of effort into making sure it can flow air properly and take the additional stresses.
The rest of the package involves a base tuning map along with various other ancillary components that have been uprated to take the additional stresses of more boost and more power. Just like any other remap from a tuning house, these have been tested rigorously both on the dyno and the open road to ensure ease of use. A few months of on-road testing was also necessary to see how the components stand up to daily heat cycling- one of the issue rarely addressed by tuners, and one of the major differences between a race-car and a road car.
