Sure. It's entirely possible to build a replica engine out of styrene, putty, tubing, etc. The limitations would be only your scratchbuilding skills, and much more important, your research materials. This is the big kicker, though. It's not the sort of thing I would attempt without good engineering drawings of the engine- and I've certainly never found a source. Picures (LOTS OF PICTURES!) are necessary also, but unless you're a professional photo interpriter, it would be nearly impossible to get reasonably accurate dimensions and angles of the engine from photos. This is a project I've always wanted to do, too- 'cept I would do a Ferrari engine- either a Testarossa or an F40. But even with numerous trips to the area Ferrari dealership, shooting out lots of rolls of film on Testarossas in various states of assembly, I still don't have nearly enough material
(course then again, maybe I am just a bit obsessive about these things....
). Still scratchbuilding like this is about 10% building skills, and 90% research.
Failing engineering drawings of the engine, the only other possible approach might be if you had a really good model of the engine in 1/24- one of Tamiya's finest efforts, say. Gather together drafting dividers, dial calipers, engineer's scale, triangles, etc and a sharp pencil, and draft your own drawings- then scale them up. Course you'd just be making a model of a model... but it would be a place to start. Good luck!