During a recent visit to GT Pro in Fullerton, CA, we were given an insight into the company’s latest tuning project. Initially known for its work on the Mitsubishi 3000GT, but increasingly moving into European circles, the company has been focusing on Audi, BMW, VW, Mercedes and Porsche.

The new R&D project includes a turbo upgrade for the N54 3.0 twin-turbo motor found in the BMW 135i, 335i, 535i, Z4 and X6. In stock trim, the engine develops 300hp and 300 lb-ft of torque.
The GT Pro turbo conversion will retain the stock turbo housings for two reasons; firstly, because space is already limited, but secondly, to make the upgrade invisible. The latter is thought to help avoid any warranty issues that may arise with new cars.
The turbo conversion will use a new compressor wheel and a modified turbine wheel to increase airflow and boost pressure.
In testing, the upgrade initially gave 40whp, but 60whp seems more realistic with the latest software. The price for the conversion is $2495 and it’s available now for purchase. Visit www.gtpro.com for contact info.