Perception can be easily affected simply by the shape of the torque curve also. A very rapid change in the rate of acceleration (steep, almost vertical, front end to a torque curve) can be deceptive and make a car feel
less quick than it really is. The 335i suffers from this in my opinion. It's near instantaneous torque and then completely flat for ages so there's no "surge"; no onset of boost; no feeling of the acceleration building whereas my MPS would build like a rampant rabbit from 2500 to 3500 rpm to a peak torque not that much higher than a 335i but it would always
feel a tonne quicker. This is why I kept checking if I'd left the handbrake on or something crazy when I test-drove the 35i - it never
fealt quick even though its figures are respectable.
I've never driven the 335D (hell, I haven't even driven my 30D yet!) so can't comment on them specifically but my modified MPS and a 335i are very close on paper but driving them back to back was chalk and cheese except my MPS couldn't deliver a 6-pot tingle as the rpms passed 5000
