From what I can gather these are a list of enignes that I have resarched and known to exist (although someone will correct me on this:
2 types of F4R 2.0L 16v engines, (one looks like this:
http://www.maxipratik.fr/medias/annonce/3662_1.jpg and one looks like this:
http://www.247spares.co.uk/res/images/engines/ref/546345/8799.jpg - one maybe actually a F3R engine)
A G8T variant (Diesel 2.2L 12v
http://d.moto.gratka.pl/auto/10024/ogl/21/4b/12995074749656_A.jpg)
A G9T variant (Diesel 2.2L 16vhttp://i77.servimg.com/u/f77/14/47/94/82/p1100214.jpg)
A Z7X variant (Petrol 3.0L 12v
http://bilder2.eazyauction.de/xxalex98xx/artikelbilder/5318.jpg - never seen one however)
A L7X variant (Petrol 3.0L 24v
http://i.ytimg.com/vi/A0A6zRCNBNE/maxresdefault.jpg)
In addition there was alleged to be a F9Q variant (Diesel - 1.9L 16v which looks like this
http://i210.photobucket.com/albums/bb288/davelowe1977/enginebay/DSCF1455.jpg) although I've never seen one for sale which probably means they were quite rare.
This is what I have determined from what I've researched. It is very likely with the engine you have a later F4R 16v 2.0L petrol variant, which is actually 140hp. I believe the later espaces came with turbocharged engines. However, if it shows more power, then it might be possible that someone modded it, but you'd need to closely scrutinize the engine bay. Have you looked for an engine plate? It might be near impossible to see however.
I hope this helps, I'm sure someone as I said previously will be more than happy to correct me.