Dynamometer Model: Raceline Development Dynamometer
Testing: Elton Lo and Scott Tsuneishi
Baseline
Pros
It's official. The Honda CR-Z is the world's first production hybrid vehicle to offer a six-speed manual transmission. Honda's sport hybrid is powered by a 1.5L i-VTEC engine that produces 122 hp and 128 lb-ft of torque and returns an impressive 37 mpg combined city and highway driving. Instead of having a separate alternator and starter motor like traditional internal combustion engines, Honda's Integrated Motor Assist (IMA) system combines the two functions in one by using a DC brushless electric motor to start the engine, accelerate the car, recharge the battery, and provide regenerative braking.
Cons
On the left side of the dash is Honda's exclusive three-mode drive system, allowing the driver to select Econ, Normal, or Sport modes to custom tailor the vehicle's performance to their preference. While a novel concept, we found that channeling through the three modes seemed to do nothing more than change the throttle response, similar to an aftermarket throttle controller. Switching to Econ mode causes the vehicle to respond sluggishly as it accelerates off the line, which includes a lethargic throttle response while shifting through the six-speed. Honda representatives refer to Sport mode as "the push-to-pass" button. We opted to keep it on the Sport mode for its more responsive nature, regardless of any diminishing fuel economy.
Notes
Because the IMA system recharges the battery under regenerative braking, our CR-Z quickly drained of electrical power assist after two dyno pulls. Our initial response was to pull the vehicle off the dyno and drive around the block to fully charge the battery after every run, but we found a more time-effective method that consisted of gently applying the brakes under deceleration while still on the dyno to regenerate the system.
HKS Silent Hi-Power Exhaust
(Center Pipe + Rear Section)
Horsepower Gain
• 2,000 to 3,500 rpm range: 2 to 3
• 3,500 to 5,500 rpm range: 2 to 4
Parts
Exhaust, mid-pipe, hardware, stickers, instructions
Tools
10-, 12-, 14-, and 17mm sockets; 10-, 12-, 14-, and 17mm open-end wrenches; ratchet; extension; crescent wrench; anti-seize; WD-40
Installation time
120 minutes
Pros
Constructed of fully polished SUS304 stainless steel, the HKS Silent Hi-Power exhaust system was designed to offer improved exhaust flow and horsepower gains over the factory unit. The Hi-Power system with its optional center pipe section features larger 50.8mm diameter piping, a built-in resonator to minimize droning, and a 65mm single-rolled tip for a sport-inspired appearance.
Cons
Removal of the factory mid-pipe is time consuming, as it requires unbolting the factory under paneling and chassis brace. Don't be a hero; ask a friend or colleague for a helping hand to speed up the removal and installation process.
Notes
We were pleasantly surprised with the deep exhaust pitch and modestly quiet decibel level. The dyno revealed an increase in horsepower and torque throughout the powerband, with a peak gain of 2.8 hp and 2.9 lb-ft of torque. We saw healthy gains of 3 to 5 hp and torque in the midrange to top end, from 3,000 rpm to redline.
HKS Racing Suction Reloaded Kit
Horsepower Gain
• 2,000 to 3,500 rpm range: 1 to 3
• 3,500 to 5,500 rpm range: 2 to 3
Parts
Intake pipe, filter, Alumite engine cover, heat shield, nuts and bolts, hardware, stickers, instructions
Tools
8-, 10-, and 12mm sockets; 8-, 10-, and 12mm open-end wrenches; ratchet; extension; screwdrivers; pliers
Installation time
50 minutes
Pros
The Reloaded intake system utilizes HKS's patented Super Funnel design and a high-flowing, dual-density polyurethane filter element for improved airflow, while the replaceable element eliminates the need to wash or re-oil the filter. Each kit comes with an aluminum heat shield and an etched HKS Alumite (sealed anodized aluminum finish) red engine cover to customize your engine bay.
Cons
While not the fault of the HKS intake or design, we failed to properly adjust the intake before closing the hood, which ended up scuffing the red anodizing on the top of the filter cage.
Notes
The new intake delivered consistent hp and torque improvements across the board, with gains of 2.8 hp and 3.4 lb-ft of torque at peak performance. The dyno also recorded top-end gains of 4 hp and 4 lb-ft of torque from 5,100 to 6,200 rpm.