Here's a pretty ridiculous question -- at least, it certainly was about a decade ago. Back in 2003, Ford's Taurus was rental-car quick at about 16 seconds flat in the quarter, and the STi was a 13-second rocket ship. But that was when Ford was content to limp along in anonymity, and Subaru was at the top of its game. Fast-forward 10 years, and this race suddenly gets a great deal closer.
SHO vs. STi
The 2013 WRX STi has 305 horsepower and weighs in at 3,200 pounds; the Ford Taurus SHO is a great deal heavier at 4,400 pounds, but comes to the party with 365 horsepower and 350 foot-pounds of torque just off idle. Both cars rock the Earth with all-wheel drive and turbochargers. The Subaru is slightly smaller when viewed from the front, and the two have about the same drag coefficient. So, aerodynamic differences are fairly minimal, with a slight edge going to the Subaru. But is that edge enough to overcome the Subaru's power disadvantage when outright power counts most?
The lighter Subaru just hole-shots the heavy Ford with its 0.2-second quicker 5.0-second 0-to-60 time. Further down the strip, the powerful SHO reels the STi in, just nosing ahead by 0.1-second at 13.7 seconds through the traps. This seems like a real driver's race, and it is -- until you realize that the Ford's 103.2 mph trap speed is 3 mph higher than the Subaru's. On the top end, these two are very, very close. With the speed governors turned off, mathematical models give the Taurus a hypothetical 165 mph top speed; the Subaru's hypothetically good for 163 mph. The gap here is no narrow that adding or removing 5 psi of air in the tires could easily make the difference between winning and losing for either car.
Food for Thought
It's almost as though Ford specifically engineered the SHO to keep up with hooligans in rice rockets -- cops who drive SHOs as interceptors can probably see the logic.