2008 Honda Civic Mugen Si

Watch the Honda Civic Mugen Si run the Streets of Willow circuit HERE

The realization hits three seconds after hurtling out of the banking, foot to the floor. Two seconds after sucking in a breath and holding it through the blind chicane. One second after the staccato left-right-left roar of the rumble strips. It hits just after the full pucker left, a millisecond behind the flick of the steering wheel that shoots the Mugen Si through the corner and out the other side, millimeters away from the track's edge and the infield runoff beyond.

Whoa! This thing handles.

And well it should. M-Tec, the company formerly known as Mugen and Honda's unofficial motorsports arm, is largely responsible for the modifications that turn a regular Civic Si sedan into a Mugen Si.

What M-Tec has done is hardly groundbreaking. After all, what makes this limited-edition special is simply a bundle of carefully selected aftermarket parts installed at the port and served with the same Honda warranty all Civics receive. But you can't argue with the results; one fast corner demonstrates that the Mugen Si is as big an improvement over the already stellar Civic Si as that Si is over the base model. It really is that good.

Why? Suspension and tires mostly. Underhood, there are no power modifications -- just the same sweet, 2.0L, 197-hp, 7800-rpm, petrol-burning grin generator. Sure they've added a sports muffler, but all you'll notice is how nasty good it wails. Body modifications, including the redesigned front bumper, side skirts, rear bumper with integrated diffuser, and adjustable rear wing are said to improve aerodynamics, but it's difficult to tell at any speed.

Not so with the upgraded tires; summer spec BFGoodrich g-Force KDW tires replace the Michelin Pilot Exaltos found on regular Si. At size 215/40ZR18, these tires have less sidewall and a wider sweet spot. What's more, they come mounted on forged alloy wheels that are 27% lighter, 1.0 in. larger in diameter, and a half inch wider than the 17x7-in. cast alloys they replace.

Stock Civic Sis, like many Hondas, are under-tired considering their performance potential, so hard driving often devolves into a fit of howling rubber and frenzied understeer. Not so with the BFG-shod Mugen Si; when pushed to the limit, the KDWs break away predictably and progressively with only a bit of squeal. Consequently, probing these outer limits in the Mugen is much easier and drama free than in the Si

Additional confidence comes from the revised suspension. The tuning is light -- lower, stiffer springs and re-valved dampers -- but the results are significant. Ride is 0.6 in. lower. Front and rear bump and rebound, both have been increased between 8- and 24%.

Behind the wheel this translates to tighter turn-in and greater clarity while cornering. The rear wheels seem to follow the fronts more closely; there is no slop or wobble in quick esses, no instability in high-g sweepers, just pure carving precision and the heady feeling of being able to chuck the Mugen into every corner and pull it clean on the other side.