We report an efficient wavelength conversion via four-wavemixing in reverse biased silicon-on-isolator p-i-n rib waveguides and demonstrate, for the first time, the conversion of a high-speed optical pseudo-random bit sequence data at 40 Gb/s. Results give a wavelength conversion efficiency of -8.6dB using a 8cm long waveguide with clear open eye on the wavelength converted signal. Conversion efficiency as functions of pump power and bias voltages has also been investigated. We show a slope efficiency close to 2 as predicted by theory.