I don't know, maybe 360 km/h... I'll try tonigth.
I told this one because I made 1'31.2xx on Trial mountain and made 1'27.9xx with the ZZII that make 910kg/740hp so I supose they accel more or less the same - the main strength of the ZZII being the acceleration.
If my memory serve, you've got the NSX S-Zero @ 444HP who can make 380-390km/h in GT4 (with individual shifting setup/aero tuning, I remember making 404km/h). But it's more than 410 hp.