Tested: 2006 Honda Civic Si

2006 Honda Civic Si
2006 Honda Civic Si in Motion
Beginning with the 1987 CRX Si, Honda’s performance moniker has been flown on five different versions in its 19 years in Canada. As the flagship model for the Civic lineup, this sixth-generation Si (eighth-gen Civic) lives up to its reputation as the performance halo for Civic enthusiasts. You might even say it exceeds its reputation.

During a heat wave this past July, I was whisked away to Japan for a sneak preview of the redesigned 2006 Civic Si Coupe. With plenty of seat time on the challenging Twin Ring Motegi Circuit and a massive autocross course set up on the infield of Honda’s high-speed test oval at their main R&D facility in rural Utsunomiya, it handily absorbed everything I threw at it. I’ll even say the Si is my early favourite for the 2006 Canadian Car of the Year. Not because one of my fellow auto scribes almost lost his lunch after a stint with me on the autocross, but because it’s everything it should be. “You have shares in Michelin?” he joked after a couple of turns. “I hate to say that I even used to autocross,” he said minutes later while peeling himself from the vehicle with a ghastly expression on his face.

It’s no secret the Si is geared toward the significant chunk of 16-to-24-year-olds that’ll be driving consumer spending for the next 30 years. More importantly, the Civic has long been held up as the flagship vehicle for the whole sport compact tuning industry. With literally hundreds of thousands, perhaps even millions, of aftermarket parts that can be purchased and installed on all generations of the Civic, it will be hard to resist for enthusiasts of the brand.

The ’99-00 model was a high point for the Si. On the other hand, the ’02-05 Si hatchback model didn’t do too well. Consequently, Honda’s decided the days of the compact three- and five-door hatchbacks are over, at least for now. It is clear, however, that the ’06 Si is for the more passionate breed of enthusiasts, many of which caught the customization bug long ago. Well, Si suitors will be pleased with the car’s factory performance, but also a stout list of features that make it a formidable foundation for tuning.

2006 Honda Civic Si
2006 Honda Civic Si Engine
Honda’s new K20Z3 DOHC i-VTEC four-cylinder engine boasts 197 bhp at 7,800 rpm (SAE standard) and 139 lb.-ft. of torque at 6,200 rpm and features balance shafts to drivetrain reduce noise, an exhaust manifold with equal length runners, drive-by-wire throttle and new mass airflow sensors for more precise tuning of the engine and intake system. Existing engine components have been fortified and the 11:1 compression engine features a straight-ported head for better flow as well as two-stage i-VTEC on all valves. A new six-speed manual transmission (a Civic first) has a 4.765:1 final drive ratio with closely spaced gears for short and precise shifts. Single carbon synchros reduce friction while a more rigid case curbs noise.

Upon firing up the ignition, your ears immediately attenuate the groovy exhaust note when pumping on the accelerator. The power curve is pretty straight from bottom to top with the VTEC changeover occurring at roughly 5,250 rpm for an extra boost of acceleration. The tuned intake and exhaust system, which makes the Si sound like a subdued Type-R, lets you know when it kicks in! There’s a feeling of endless acceleration as the needle rises all the way to peak at 8,000 rpm as you’re pulled back into the comfy dual-density sport seats that are even better than the current RSX Type-S ones.

That one engineer let it slip the new K-series in the Si is actually designed for 220 hp basically sweetens the deal for potential buyers. Simply installing a higher-flowing exhaust (you’ll want to keep the intake because of the special valve timing and i-VTEC duties) and removing the balance shafts ought to tap into that reserve to the tune of 10-12 horsepower. Add a new air filter, some platinum plugs maybe, and you’re on your way to the races!

Not much was done to alter the Si’s exterior during the concept-to-production stages, including the low windshield angle, crouching form, short wheelbase and aggressive rear spoiler that lowers the coefficient of drag by three percent (versus no spoiler).

2006 Honda Civic Si
2006 Honda Civic Si Rear Quarter

The windshield angle is not only two degrees sharper than the sedan; it’s also the fastest glass angle of any past or present Honda vehicle, including the Acura NSX. Aerodynamically, the Si further benefits from a sectioned integrated front chin spoiler that assists steering and cools the 11.8-inch front disc brakes as well. The rear discs are 10.2 inches in diameter.

As for the unibody frame, an internal bulkhead crossmember, rear upper arm bracket and thicker rear stabilizer bar brackets were added to the crossmember where the rear suspension mounts to give additional strength for aftermarket modifications. Getting the suspension setup just right was critical for the engineers, who did the actual tuning on the Motegi circuit. To this end, damper force is 45 percent greater than basic models and spring rates are up 17 percent. The stabilizer bars are dramatically different as well. In the front is a solid bar, however, the rear one is hollow with a 5mm increase in diameter to 17mm. All of this gives the Si 30 percent more roll stiffness over the other models.

Developed exclusively for the Si, the 17-inch standard alloy rims are paired with 215/45R17 Michelin Pilot HX MXM4 all-season tires. These are the largest standard tires ever offered on a Civic and provided a great deal of dry and wet traction in my opinion. Honda is offering an 18-inch Honda Factory Performance wheel option along with 18-inch Michelin Pilot Exalto PE2 summer performance tires.

When pushed hard on the autocross, the Si understeers in tight corners, but the four-channel ABS brakes with EBD (taken from the RSX Type-S parts bin) are up to the task of scrubbing speed before entering a corner. Short bursts of acceleration evoke an immediate reaction from the potent four-banger while a new Helical-type limited-slip differential (taken from the JDM Honda Integra Type-R) splits power evenly so it can be applied sooner in turn exits and reduce the amount of steering correction. I was even able to invoke a bit of understeer at times; and, if you can match the revs on your down-shifts, you will enjoy exciting power throughout whole turns.

2006 Honda Civic Si
2006 Honda Civic Si Shift Knob

On the much bigger Motegi circuit, the LSD really shines and the Si’s quick steering ratio (compared to the other models) translates into smooth corner entries with an excellent on-centre feel at all speeds. The brakes offer good initial bite, however, they did start to fade after several laps because of our abusive journalist tendencies and the longer straight-aways. Second and third gear offer hard acceleration, but I should mention that I rarely used fifth gear at Motegi since the back straight had a 120-km/h slalom course setup on it. Coming into the turn one hairpin after the shorter front straight in fourth gear (somewhere between 125-140 km/h) was plenty fast too! It also underscores the intention of the sixth forward gear. That is, it’s really for high-economy highway cruising.

Inside, the new two-tier dash and heads-up interface is one of the more intuitive and useful ones I’e seen on cars in this range. A neat feature here is the digital speed gauge with built-in rev limit indicator that helps minimize eye movement during aggressive driving.

2006 Honda Civic Si
2006 Honda Civic Si Instrumentation

The shift light starts blinking at 7,400 rpm to indicate the approaching red zone and goes solid at 8,000 rpm to allow rapid gear shifts without having to look at the tachometer.

2006 Honda Civic Si
2006 Honda Civic Si Interior
There’s an ambient console light that’s color-keyed to give the interior a personalized atmosphere at night; and, a surprising standard 350-watt seven-speaker CD/MP3/WMA audio system audio system with eight-inch sub, speed-sensitive volume control and auxiliary input jack for MP3 players. An advanced 2-DIN voice recognition navigation system is also available.

The 2006 Honda Civic Si was a real joy to drive! With excellent performance and great looks inside and out, it’s a great package that has potential to be even better. It’s also nice to see Honda getting back into the sport comp game where domestic manufacturers have been growing roots for at least a half decade. The performance-to-dollar value of this car is high right now. The aftermarket is all amped over this car too! But hear this: the new VW Golf GTI will surely put up a good fight when it comes to town in the not so distant future. In fact, Euro platforms like VW are coming back to the forefront of the sport tuning scene with a vengeance, and bringing with them heavy-hitters like Audi, BMW and Mercedes.

2006 Honda Civic Si
2006 Honda Civic Si Front Quarter

I have no doubt that smart Canadian consumers will love the new Civic; and, Honda will likely sell out of Si’s faster than they can be brought in. From what I’ve gathered about Honda nuts and other brand defectors is that they’re already in tune with what’s going on. Many are probably already strategizing about their own series mods for this car. Most will be young and enthusiastic and, no doubt, ready to get their hands dirty. It’s these buyers, the ones who best understand Honda’s Challenging Spirit, and who hold the Si above other marques, that will appreciate it the most and take it to uncharted levels in the aftermarket. But, even when sold as is, the new Si will be hard to compete with.

[Disclaimer: Always consult your dealer about performing any modifications to your vehicle. In some cases, you can accomplish what you want to without voiding your warranty. No modification to any vehicle shall become a hazard to drivers and passengers of it, or any other vehicles it shares the road with.]


Price Range: TBA
Body Type: 2-door coupe
Layout: Front engine, FWD
Engine: 197 bhp (SAE net), 139 lb-ft, 2.0L, 16-valve, DOHC, i-VTEC, inline-4
Transmission: 6-speed manual
Brakes: disc/disc, ABS and EBD
Curb Weight: 1,305 kg (2,877 lbs)
Acceleration: 7.3 sec. (est. 0-100 km/h) on summer tires
Top Speed: N/A
Seating Capacity: 4 (2+2)
Cargo Volume: 325 L (11.5 cu-ft)
Fuel Economy: 22/31 mpg (city/hwy)
Warranty: 48/100,000 comprehensive
Direct Competitors: VW Golf GTI, Mazda3 Sport, Chevy Cobalt SS, Saturn Ion Redline, Nissan Sentra SE-R Spec V
Website: honda.ca