Although some Ascona's were upgraded for higher performance (a memorable "Car and Driver" magazine project is still in existence), most Ascona's were driven as commuter vehicles, and very few are around today.
All Asconas, including the 2-door sedan, the 4-door sedan, and the station wagon versions, shared the same 1.9 liter driveline with the 1971-1975 Opel Manta.
Many driveline parts are available from specialty Opel parts retailers, and technical assistance can be found from the original Opel 1971-1974 factory service manuals** or from referring to "Tech Tips" section of this website where parts are shared with the Opel Manta. Body and interior parts are becoming harder to find for the Ascona.
**The 1975 Opel Service manual is primarily of value, as a supplement for fuel-injected 1975 Opels only.