Erm, I'd have thought your biggest problem would be how to stop the engine melting!

A standard XR3i engine is not really suitable for turbocharging (unless it's REALLY light pressure), the compression ratio is too high. You either need low-compression pistions (i.e. an RST bottom end) or a de-compression plate (not a favoured solution).

Even once this is done, I doubt that the standard system is capable of measuring that large a volume of air and even if it could, chances are that the injectors wouldn't be unable to supply enough fuel...meaning a lean mixture...meaning a melted engine!

It might be easier to fit an RS Turbo engine complete.