A guy around here built a "357ti". Took a '96 318ti and stuffed a nicely built LS1 in it. Was putting out a bit over 450hp as I recall.
Unfortunately on it's first trip to the track a Mustang busted it's oil pan in front of him and sent him into a corner and over the berm. He came out of it fine, but the 357ti was toast. Wished I would've seen it in person before it got wrecked. Apparently was insanely quick, sounded awesome, and a total blast to drive.
Though there's also a ti that's in Germany that's got the V12 out of an 850CSi in it. I imagine that'd be good fun as well.
Cosmos Black/Black 1995 540iA M-Sport
BMW Individual Exclusive Edition, 1 of 65 total, 9/25/95 Build