The diode is a cheap method of upping the boost on a 1.8T. You solder a new one in that connects to the waste gate and the boost pressure increases and then you can control it with an Electronic Boost Controller. It is an alternative to buying a chip. If he has a diode then he isn't chipped.
The only 1.8Ts that have a larger turbo are the AMUs found on Audi TTs. They have K04s. The 1.8T 20v can make good power, but not great torque. The 2.0TSI is a much better engine. Plus the timing belts (on the 1.8Ts seem to randomly snap in half.
The only 1.8Ts that have a larger turbo are the AMUs found on Audi TTs. They have K04s. The 1.8T 20v can make good power, but not great torque. The 2.0TSI is a much better engine. Plus the timing belts (on the 1.8Ts seem to randomly snap in half.