Give this 550-hp V10 Hartge BMW Z4 a home

Here at Autoblog, we cherish the simple things in life. Like a cold beer on a hot afternoon, spending the holidays with family or stuffing an oversized engine into a little sportscar. It's a time-honored tradition, and this example is no less worthy than any that has come before. Evidently unsatisfied with the S54B32 inline-six powering the top-of-the-line BMW Z4 M, one European enthusiast dropped in the 5.0-liter V10 from the BMW M5 and M6 into his little BMW Z4. But even the stock 507 horses from the high-revving ten wasn't enough for this Bimmerphile, so he went with Hartge's 550-hp version, complemented by the tuner's own 20-inch rims, but, worryingly, no sign of upgraded brakes to go with the 200+ extra horsepower. The converted roadster cost €170k new, but is now on the market for under €98k (tax in), or about $138,000 in American greenbacks. A hefty sum for sure, but can you really put a price on 0-60 in under 4?