First off, I think you will find the 350Nm is actually at the wheels not engine(gearbox/diff torque multiplication), an NA 20V is not going to put out that sort of torque at the flywheel.

I have been for a spin in a NA 20V that put out 132kw at the wheels(177hp) so very similar to the power out you are talking about. Basically it worked between 5000rpm and 8500rpm, below 5000rpm it was slow as and fell into a huge hole, in the 5-8.5K rpm band it was bloody fast, but this was also because it was ina clubman and ultra close gear ratios courtesy of a Quaife 60G 6 speed sequential gearbox with full throttle clutchless upshifting.