Oh Miss Tali's supplied the schematics! Here, I'll pass them along: [schematics download link]
This is fantastic meeting other technical brainiacs, even if the circumstances could be better off for everyone. As for the torpedo, theoretically it could and it's possible to construct something similar with the proper supplies at one's disposal. All it takes is a guidance system and an internal drive for propulsion.
It could even be something rudimentary? I blew up part of Texas once with an atom smasher, but it was a small part and they really shouldn't have thrown such a bloody fuss over it. I'm indisposed at present...ahem...but if I could find a way to send some supplies and diagrams, maybe you lot could throw it together and see if Tali and her lot can find a way to get it in there and make it go boom?