

The engine gets new belt driven twin-superchargers with a limited boost pressure of 0.48 bar, the heat insulated intake manifold have been redesigned to provide the engine with pre-compressed air and the it also gets two high performance air filters and eight larger injectors. The extra heat generated from the additional power is cooled with a higher capacity coolant system.
The subtle interior modifications include a new flat bottomed sports steering wheel featuring leather and carbon fibre materials as well as carbon-fibre shift paddles.The RDX badgeless front end lends the Fox with a Golf GTI-look while the new Audi S6 daylight running lights are an optional extra. The side sills and rear diffuser match perfectly and RDX has left the rear bumper without tailpipe cut-outs, leaving that to the discretion of their customers.
The body kit is fully TÜV certified and approved and costs just over Euro 615.
For the upgraded tuning package Renntech have re-worked the ECU software and added a less restrictive motorsports-style exhaust system to get the extra ponies to the new Renntech Signature 10-spoke, 3 piece performance wheels.
For an extra bit of added spice the tuner has also provided a nice little video in which you can hear the engine.
The 2009 Roush RTC should arrive at dealers shortly and is expected to set you back USD 13,375 for the base package. The optional chrome ROUSHcharger for a total of 430 bhp costs another USD 6,250.
Ford will be releasing a brand new Mustang starting in the 2010 model year, so this Roush will be one of the last for the current S-197 body style.
Options:
Looking closely between the two kits the Street Rocket sheds the excessive wide body fender and quarter panel wheel arch flares. As a result, the front bumper lower spoiler gets redesigned to fit the new width dimensions of the body and the rear bumper gets simplified as well in the same fashion. However, the overall design details of the front and rear bumpers remains the same. Gone are the roof spoiler extensions which extend down the side of the D-pillar. Sporting a brandy wine color the interior gets splashed with matching red accents and stitching.
Overall, this looks like a less bloated version which is a big improvement.