The best indoor kart racing facility in the Southwest is hosting the final round of its Challenge GP race series this coming Sunday at K1 Speed in Phoenix, Arizona. European style karting has taken the southwest by storm with the K1 Speed indoor electric race karts. The current track layout is ran in the reverse direction for this 4 race series, which an overall points champion will be announced after this weekends race, then we will move to a 6 race format for the second half of the 2011 race season. Sign-ups will begin at 6:30 PM and qualifying will start at 7:00 PM with double qualifying rounds and corresponding main event rounds giving drivers of all skill levels and abilities the chance to compete against one another. Come out this Sunday June 12th and check out the K1 Speed Challenge GP Race series in Phoenix, Arizona – located just south of Glendale and Scottsdale.