The 1.8 vectra is DOHC if I remember rightly, that's BAD news, at the very least you'll have bent valves. Which means head off, new gaskets, cam belt etc.
At the very worst the valves have smashed one or more of the pistons and bent a rod or two and your engine is a write off.
Most likely is bent valves, broken buckets, possible camshaft and probably holed pistons and bent rods.
If you love the car source a 2nd hand engine.
Doing 60 when it went? Even if you dumped the clutch at the second it went........
Dave the wrench.
January 2009