The site is down right now, but later try
Mazda6 Club. Try looking for the model's other name, the
Atenza for more information too.
Also, from the
Urban Racer website:
"GReddy loaded up a sexy Mazda Atenza (Mazda6) with a host of performance upgrades and visual tweaks to turn the Atenza into a showstopper on and off the track. Utilizing a newly developed GReddy T51 turbo kit, the Atenza boosts to 241 ps (238 hp) with the assistance of larger fuel injectors and a number of GReddy performance electronics."
I don't think that GReddy plans on releasing this kit to the US though.