you can fit the six under the hood. plenty of room. you'll need to swap the trannies also. or get a tranny from an auto 325 (do they make an adaptor so he wont' have to do a tranny swap?) you will need the fuel system, ECU and all that good stuff. the drive shafts, and rear diff from the 325... basically take everything that make a 325 go and put it in the 318i... I don't know if it all would fit right (different wheelbases?) I have been thinking of doing a swap from a 325 my self... been trying to research it, and this is all I've come up with. hope i helped.
No posers, hacks or sellouts allowed.
"Only posers die..." - Stevo "SLC Punk!"