After the unibody is completed, X3 and X5/6 assembly lines diverge. The X3 bodies move through an underground tunnel to a separate assembly hall that isn't open to tours just yet. The tour follows the X5/6 line, and we watch as around 8000 parts are attached.

The genius in the assembly line is that these vehicles are built and assembled in invoice order. It's uncommon to see an X5/6 that's identical to the one in front or behind it. Such flexibility demands intense logistical planning, which BMW manages with "just in time" inventory. Parts are delivered very shortly before they're needed; the sitting inventory is measured in hours.

It's difficult to comprehend the complexity of the modern car until you see how one is built. In the X5/6's case, for example, it takes more than 7000 employees and more than 380 robots. Its 90-pound wiring harness needs to be heated to 100 degrees to make it pliable enough for a six-person team to run it through the car. Marrying the powertrain to the body takes about three minutes. An X5/6 takes 30 hours of work to complete (with time spent sitting, the total build time is around three-and-a-half days). And, at the end of a shift, two vehicles selected at random go through an exhaustive eight-hour quality audit.

Homeward Bound
Performance Center Delivery has been a runaway success for BMW, and it's easy to see why. It makes the new-car experience something special -- you're not driving home from the dealer tired from hours of haggling. Instead, after driving lessons, education about the brand, and an astounding look into the car-building process, you're embarking on the best kind of journey you can take with a new car: a road trip.

That's why associate photo editor Mike Shaffer is joining me tonight. You see, we have a bet with executive editor Ed Loh. It goes: We can cover the 3000 miles that separate BMW's operation in Spartanburg and Los Angeles before Monday morning, giving us four days to zigzag through the South and Southwest, hunting for interesting sights, and more important, food.

We'll make it, no problem. Stay tuned for Part 2, the adventure back home.