I originally had a Mk3 Astra SRi that came with the 2.0L OHC engine (same as the MPFI sunbirds). I was going to do a turbo conversion and restore the bodyshell but it turned out to have serious rust in structual areas so I junked the car except for the suspension and drivetrain. I then found myself another Mk3, this time a little 1.4L version but with an immaculate rust free bodyshell. Within a couple of hours of getting it home the interior was ripped out! I since found out that GM did a turbo version of the OHC engine in the Pontiac Sunbird GT. Thanks to members of this site I now have all the turbo stuff for my engine!