That 425 hp busa has the same power to weight ratio that Chad's car would have if he lost the stereo, so acceleration would be similar. I don't know about aerodynamics over 200. SVSi says that while cars have the edge at 130+ to about 200/210, bikes take it back, so I don't think his car could hit 250s, but who the hell knows.
A vehicle will not "take it back" at higher speeds because aerodrag is an ever increasing force with is defined solely by the shape of the body, the air conditions and the velocity. Each vehicle follows the same laws of physics.
What it boils down to at high speeds is which vehicle has reserve HP after overcoming aerodrag. Theoretically, if a car had twice the aerodrag as a bike (which is close to the real case) at all speeds, then the car would have to have twice the RWHP as the bike to make their drag/power ratio equal.
A Busa with factory bodywork has a CdA = 3.37. A Z06 Vette (numbers I know) has a CdA = 6.60. The Viper CdA would probably be about 7.0. That's 7.0/3.37 = 2.08 times ... about twice.
A Busa could theoretically go 265 mph with 425 RWHP. A car with twice the CdA and which has more rolling resistance due to much more weigh would need 1000 RWHP ... a little more than twice the HP due to higher rolling resistance. Rolling resistance for the Busa need 11 RWHP and the Viper would need about 120 more RWHP. 2.08 x 425 = 850 + 120 = 970 ... close cross check.
So, the Viper would need about 1000 RWHP to top out at the same speed as a 425 RWHP Busa. Of course
the gearing would have to be optimized to reach the best possible top speed.