Both are stock turbos and full bolt on, 100% E85. The n54 has a custom tune, the B58 a OTS e85 tune IIRC.
The run was for money. The n54 won.
The b58 should win, not because of the engine or turbo, but drivetrain and chassis. One is a ~5k car, one is a 25k at minimum and ~10+ years newer.
The point being is the B58 is an OEM single turbo and makes less whp and wtq than n54 OEM twins both maxed out on E85, I could be wrong. The B58 is the successor to the N55. The claim a mild tune B58 would wipe an n54 with a ton of money invested is interesting. A ton of money in an n54 would at be a single turbo on E85 for instance. Not an n54 2k pure turbo twins with no tune running an OTS MHD map made for the stock turbos. A mild tune on an B58 I would, and I think most would, think is FBO on 93 OTS map maybe E30? Above that no way it is considered 'mild' vs an n54 with 'a ton of money sunk into it'
The S58 is the spiritual successor to the n54 and is a hell of an engine. That engine is going to hurt people's ego