Honda CR-Z Mugen Concept

There is something gloriously irreverent about the Honda CR-Z Mugen. The exhaust is obnoxiously loud, making the kind of noise a child might make while pretending to be a car. It's not what you expect of Japanese engineering, but this Mugen wasn't designed to be subtle.

Commissioned by Honda U.K., Mugen has spent more than $250,000 imagining what could be achieved if you add spice to the CR-Z's homely recipe. It's a marketing stunt, but it's also a taste of what's to come when Honda finally gets around to producing a hot version of its hybrid coupe.

The Honda CR-Z Mugen will be officially unveiled at the Goodwood Festival of Speed at the end of the month, but Inside Line was invited to an exclusive test of the car at the Rockingham Motor Speedway in the heart of England. Just 10 years old, Rockingham blends an oval with an infield section reminiscent of Daytona.

The Mugen Experiment
Mugen is in an enviable position. Founded in 1973 by Hirotoshi Honda, the son of Honda founder Soichiro Honda, it has always posed as the mother ship's naughty sibling. While technically independent of Honda Motor, Mugen is owned by the Honda family and Hirotoshi's baby enjoys a special relationship with dad's creation.

"We can try things that Honda can't," says Colin Whittamore, general manager of Mugen Euro. "We'll often be used to test a concept. If it doesn't work, they can always say it was Mugen's idea."

Whittamore heads a six-strong team of engineers in Mugen Euro's U.K. headquarters. Having successfully engineered limited-edition versions of the European-spec Civic Type R, his team began work on the Honda CR-Z Mugen last October. The brief was simple: to create a CR-Z capable of matching the performance of the outgoing Civic Type R.

Hybrid Rules OK
Mugen took an early decision to persist with the IMA electric motor system. "The advantage of an electric motor is that it gives you instant torque early in the rev range," says Whittamore. "The plan was then to increase the torque provided by the engine in a progressive manner." While the standard CR-Z's torque peaks at a lowly 1,500 rpm, the Mugen maxes out at 6,000 rpm.

The Mugen boss likes to describe his baby as "a Type R with a conscience.

The key to this transformation lies with the introduction of a Rotrex supercharger. Whittamore admits that Mugen looked at several different options, including turbocharging, before settling on a blower. "We wanted an integrated, engineered solution. We see ourselves as sitting between the aftermarket and an OEM."

The net result was the somewhat pretentiously titled Mugen Integrated Centrifugal Forced-induction system, or iCF for short. By rewriting the ECU, Mugen was able to integrate the different systems and retune the IMA system to be more performance-focused. The standard 1.5-liter engine was also stripped and rebuilt and although Whittamore is cagey about the details, he admits the pistons and rods are new.

The system is still under development but the most recent dyno figures show 197 horsepower at 6,000 rpm and 161 pound-feet of torque. That's 75 hp and 33 lb-ft more than a standard CR-Z. And there is, says Whittamore, much more to come.

More Than Just a Motor
Mugen might be most famous for its engines — the company even won the Monaco Grand Prix with Ligier — but this is not just a dyno job. The Mugen CR-Z sheds more than 100 pounds and is down to 2,392 pounds, thanks to the junking of the rear seats and the introduction of a carbon-fiber hood and doors. The doors each weigh 34 pounds less than their steel equivalent, but Whittamore admits they're prohibitively expensive and could never become a production reality. The forged Mugen GP 17-inch rims, though, are surely a must-have.

Also joining the party are Mugen front and rear spoilers, side skirts and a laughable rear wing pinched from the Japanese aftermarket catalog. The normally effeminate CR-Z wears the spoilers and skirts well, although we're less convinced by the wing. With no trunk to latch onto, Mugen stuck it to the top of the roof, where it looks like an afterthought and compromises the squat, pert aesthetic. For what it's worth, we're not too keen on the triangular tailpipe either, but such things are always a matter of taste.

Inside, chunky Recaros replace the standard seats, there's a "weighted" aluminum gear knob, a carbon rearview mirror and a triplet of analog dials displaying the temperature of the oil and water and the oil pressure. They perch periscopelike on the fascia and are a constant reminder, should such a thing be needed, that you're driving something special.

The Experience
Enough of the technical chat — let's hit the circuit. Given that this is the only car in existence and it's needed at the Goodwood Festival of Speed in a few days, the decision to let an enthusiastic hack loose on a track seems like an extraordinary act of bravery, but one that's to be admired.

By the end of the pit lane, the impact of the changes is self-evident. The modest response of the standard CR-Z has been replaced by something much more urgent. There are no official performance figures for this car but Mugen reckons it should match the European Civic Type R's 0-60 sprint of 6.6 seconds, and that feels about right. It's sport compact quick, not sports car rapid.

It takes a little time to get acclimatized. Despite the combination of an electric motor and a supercharger, the Mugen still needs working hard to deliver its best. It doesn't really spring to life until you hit 4,000 rpm and tails off dramatically above 6,000 rpm, 500 rpm before the rev limiter intervenes. Mugen may have been anxious to avoid a car with a "pronounced VTEC" effect and instead produced an engine with a relatively narrow performance band. It's a relief to discover the manual gearbox is as slick and positive as ever.

While Whittamore admits that the engine "is at the beginning, not the end of its development," the brakes are nothing less than superb. Mugen introduced four-piston front calipers and 12.6-inch grooved and vented front discs. Even after 15 minutes of provocation on a circuit that's heavy on brakes, they showed little sign of fade.

Although the brakes are unique to this car, the suspension components were plundered from Mugen's parts catalog and were originally developed at the Motegi circuit in Japan. The front track has been widened, while stiffer springs all-round are matched with five-way adjustable dampers. The latter offer five different "clicks" and change both compression and rebound damping. They help control the movement of the Yokohama AO48 track-day tires, measuring 215/45 R17 front and rear.

Now It's a Sport Coupe
These changes are enough to transform the character of the CR-Z. The electrohydraulic steering — inert in the standard car — is brought to life and turn-in is much sharper. It can also now be steered on the throttle. A subtle lift on turn-in is enough to coax the rear around a few degrees and set the Honda up for the apex. It's fun without being unruly, and it's a trait that should translate well to the road.

Given the rubber, it's no surprise to discover a dramatic increase in grip, at least in the dry. The Mugen still understeers, of course, but it hangs on remarkably well. It's also happy to be hustled, especially in slow corners. We only drove on the track, so it's difficult to judge how the ride would play out on the road, but the adjustable shocks should help.

Mugen is keen to present the car as a road tool that can double as a track-day toy. It has therefore retained the three-mode system from the standard car. In Sport mode you get the full-fat Mugen experience; Normal offers something reminiscent of Sport in the standard CR-Z; while Eco neuters everything to minimize consumption. "The supercharger is still active in Eco," admits Whittamore, "but everything's been optimized for low consumption."

The Mugen boss likes to describe his baby as "a Type R with a conscience."

What Now?
Although Honda has committed to building a sportier version of the CR-Z sometime in the future, it is probably a couple of years away. For now, Mugen offers the quickest route to market for an exciting, semi-official car, and there is a clear precedent. Last time Mugen produced a "one-off" for Honda U.K. it turned into a limited-production run of first 20 and then 200 cars.

You get the impression that both parties would like this concept to succeed, but there is a problem. To build the concept, Mugen had to buy a finished car and junk high-cost components, such as the brakes, suspension and seats. That's both expensive and environmentally dubious. Mugen parts are also far from cheap. The body kit (including the wheels) currently retails for $4,200, while the suspension costs $10,400, and that's before you consider the engine conversion, the interior bits and the carbon-fiber doors.

Nevertheless, Whittamore is optimistic that Mugen could offer a production reality modeled on the concept for around $50K, compared with the $28,300 entry price for a CR-Z in the U.K. At such a price, the Honda CR-Z Mugen would compete against such European luminaries as the VW Scirocco R and the Audi TT. It is less powerful and sophisticated, but it would offer greater exclusivity and, arguably, more character.

It's hard to imagine that Honda wouldn't find customers for such a car. The global interest in tuned CR-Zs is huge and reaffirms the loyal fan base that continues to exist for hot Hondas. Given the draught of performance models from the mother ship, fans are looking for inspiration and in Mugen, they might just have found a winner.

Edmunds attended a manufacturer-sponsored event, to which selected members of the press were invited, to facilitate this report.