I've heard in another forum that may by just boring your engine to the m54b30 boring size, you might be able to increase power. it won't be the same but it's pretty close to the specs. but I'm not sure how that would work out in that u will still need to figure out the gear rations, ECU,.. etc. I don't tell you to buy a m since I know that's also pretty expensive. so maybe just go around and check until you find out how to do it yourself. remember that the guy who added a 2jz on his z4 did it all by himself, so the only advice is to research and try to learn as much as possible to do it yourself.