Just read it in my December Road & Track that I got yesterday.
Red shows that there is a difference in the Mugen Si's suspension and stock FA5 suspension.Limited to a run of only 1000 for the 2008 model year and available exclusively in the Fiji Blue Pearl seen here, Honda's Civic Mugen Si features 27-percent-lighter-than-stock forged alloy wheels shod with highly adhesive BFGoodrich g-Force KDW 215/40ZR-18 rubber, stiffened springs and shocks, and a retuned sport exhaust. Other highlights include new bodywork (front spoiler, side skirts, rear diffuser bumper and a large rear wing), Mugen badging and an aluminum shift knob.
Exclusivity does have its price, however, as this Mugen edition retails for just shy of $30,000; in comparison, a standard Civic Si sedan with navigation, XM satellite radio and high-performance tires has an MSRP of $23,240.
From a performance standpoint, the Mugen-ized car's improved suspension allowed it to post an impressive 0.92g in our skidpad test versus the 0.87g we achieved in a stock Civic Si sedan tested back in our June issue. The better-breathing exhaust adds about 5 horsepower, according to Honda, but this isn't enough to improve acceleration times as it performed nearly identically to the standard car.