The review of windingroad confirm the limitation in top speed.

http://www.windingroad.com/reviews-p...-g35-bmw-330i/

The Infiniti engine certainly suggests as much. With an extra half-liter and precisely 20 percent more horsepower than the 330i, the Infiniti’s redesigned 3.5-liter V-6 feels more broadly muscular than before, especially in its upper register. That strength comes through in a smoking 5.2-second run from 0 to 60 mph, a significant eight-tenths quicker than the BMW. From there the Infiniti surges to an electronically limited 133-mph top speed.