According to the World Record Academy, the Maxximus G-Force is the fastest street car on earth. It currently has three world records, 0-60mph in 2.134 seconds, 0-100mph in 4.541 seconds, and 0-100mph-0 in 8.861 seconds. The Maxximus G-Force is a modified British Ultima GTR which can be purchased as a turn-key car or as a kit to customize as the owner desires.

Currently the car runs a 7.0L Chevy V8 with twin turbochargers pushing the power to 1,600 horsepower. Kirby spent three and a half years re-engineering the Ultima chassis to fit the engine and necessary plumbing for turbos. Several blown clutches led the team away from a traditional manual transmission and instead to a three-speed sequential transmission. The Maxximus G-Force can do 80mph in first gear. Braking is done through six-piston AP Racing calipers and 14 inch cross-drilled discs. The car weights 2,700 pounds and will set back the owner $3 million dollars. It is reported the car has been sold to a buyer in the Middle East.

Source: Jalopnik and Motor Trend

Underground Racing has produced a twin turbo Lamborghini Gallardo producing 1300 horsepower. All this power has created the world’s fastest Gallardo.

I have listed the good parts of the video incase you want to go straight to the good stuff.
1:00 – Gallardo runs a 9.524 @ 167.63 mph
1:30 – Gallardo runs a 9.113 @ 169.00 mph
2:00 – Photo slideshow of the Gallardo and some of the other projects Underground Racing worked on. I could be wrong but both times the Gallardo seems to get a horrible launch.

Source: TMRtuned

2009 Subaru Impreza WRX STI built by Crawford Performance putting out 566 whp and 611 torque.

A previous video

Source: Jalopnik