I am not 100% sure. We (VTT) have gone through an evolution on our perspective with N54 test mules. I *think* this engine was original to the car but am not sure. There was a phase that we thought picking up cheap N54's and thrashing them was a solid method (at this time all the built motors were very problematic). We test hardware very very hard so this just resulted in us blowing up more N54's than just about anyone else. Now, at least for a test car, we definitely go with fully built. Back to this car -we have an engine build in process, so it won't be too long before it's able to be used for testing again.