In this case having two versus one turbo does not mean more means better.
Originally Posted by kanar200
the reason is that it would be probably single turbo and 35d is double/twin-turbo (whatever the name), 35d US spec was downgraded in terms of power in comparison to Euro spec; 40d is double/twin-turbo and has 306 BHP right now, it is likely it will be more powerful in 2013/2014
The N54 engine was a parallel twin-turbochargers while the N55 is a single twin scroll turbocharger. Both engines produced same output but the N55 was more fuel efficient, lower emissions, less turbo lag.
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