In most corsa they do fit 2.0L engine from Astra GSI or from a calibra there the most common! For a turbo conversion is much more expensive a rare but a simple Corsa GSI does not to 60MPH in 9.1 SEC so not far from an ST. GSI may only be a 1.6 L from a Tigra and only producing 106 BHP is cause the Corsa is much lighter than the ST and also have smaller wheel which make it a bit quicker but the handle on the GSI is far from good!