hi i want to buy a 4x4 but dont know anything about reability and if it is posible to be functional for every day ....i have mild tune a 1.1 seicento abarth before some years is the engine the same ? is it better brop in a 1.2 60 hp ? any other problems i should know ? (electrics - suspension etc ? )
what speeds for travel ? is it possible to travel with 140 km/h

Yes its possible to fit a bigger engine..

But you may as well buy a modern car

I used my 1.0 4x4 Panda daily with no major problems, had the gear linkage fall off once but cable tied it back on until I fitted a new bush... as with a lot of old cars you do your maintenance and it pays off (usually)! You can do 140km/h but I always found 110km/h slightly more comfortable, and it's the speed limit here in the UK anyway (around 70mph on a motorway!), although I now have a 1.2 16v in my 4x4 Panda and it'll do 170km/h... scary at that speed mind, haha!