The fastest Subaru WRX STI (street-legal) built by Tensai ( United Arab Emirates ) took a quarter-mile run in 8.9 seconds, starting from 0 to 60 mph almost in 1.9 seconds, making it the fastest street-legal modified Subaru STI in the world so far.
The total cost for transforming a new Subaru WRX STI to a real beast exceeded USD $60,000 excluding the car price 😉.
Estimated prices of some modification parts:
Willall Stage X 2.5L Subaru Billet Aluminum Short Block $15,000
ETS 2-Bolt Rotated Turbo Kit for Subaru STI 08-14 $5,500
Engine Management Systems MoTeC M150 $5,500
Xshift +plus Subaru triple clutch sequential gearbox STI 6 speed $13,600 +
Motec C1212 Race Kits Display $3,600