If engine is not swapped, check "tikkli" / info-plate inside bonnet, which also have engine model number.
Also, if it's 90s model and auto transmission, then it might be 3 speed forward. There's no over drive or 4th gear. After 60km/h speed where car gets into 3rd gear, more speed is based on engine speed. On 80km/h with 6000rpm, you will face this issue.
I own one, 660cc turbo with manual 5speed gearbox 
EDIT: looks like someone dib up pretty old thread 