Through extensive research and testing, HKS engineers developed an all-new intake camshaft to work seamlessly with the variable-valve timing found in the Mitsubishi Evolution IX powerplant. Recently debuted in North America, the new HKS EVO intake camshaft features 272 degrees of duration and 10.8mm of lift. When combined with the HKS 272-degree 4G63 exhaust camshaft, this combo offers promising results to consumers as horsepower and torque gains are significantly improved across the powerband. Both intake and exhaust camshafts are compatible with the factory MIVEC 4G63 valvetrain.
Mitsubishi Innovative Valve Timing Electronic Control System, or otherwise simply known as MIVEC, alters the timing, duration and lift of the intake valve as the MIVEC switching mechanism phases between low-speed and high-speed profiles on the camshaft. At low speeds, the MIVEC cam profile displays a smaller low-lift and mid-lift overlap in which the two intake valves of each cylinder have a different lift. The end result is a MIVEC system, which aids in fuel economy, emissions (reduced internal EGR) and enables the 4G63 to display excellent bottom end torque. At higher rpms, the MIVEC system lengthens the valve timing in which both intake valves have equally high lifts. This high-speed mode increases the valve lift range which creates a beneficial increase in intake air volume and horsepower.
HKS Performance engineers designed the EVO IX bump sticks with the newest in technological CAD design to meet or exceed OEM quality camshafts. Using a billet core construction, each camshaft is surface treated with a high nickel content iron alloy outer shell. This specialized hardened alloy material alleviates camshaft lobe wear while maintaining an identical metallurgy to the factory roller type tappets found in the EVO IX 4G63 powerplant. The MIVEC cam was designed with a lightweight hollow core to maximize rotational efficiency as the factory valvetrain spins to the tune of 7600 rpm.
When it finally came down to testing the camshafts, we decided upon simulating a typical scenario that involves the average reader and their newly purchased EVO. Our game plan was to simply install the camshafts and spin the dyno without the aid of an aftermarket fuel management system or boost controller. Why the simple install, you ask? For obvious reasons we wanted to see firsthand the camshafts true potential in gaining both horsepower and torque before any tuning was performed but more importantly we were faced with the million dollar question on whether these HKS camshaft were truly streetable.
A quick search for a test subject netted us with an EVO MR SE already equipped with an HKS Racing Reloaded Suction intake and HKS Spec-R exhaust. Strapped to the dyno, the EVO spun the rollers to the tune of 247.5 hp and 239.3 lb-ft of torque. A respectable baseline run for an MR equipped with a filter and cat-back exhaust. After spending a few hours alongside Research & Development Manager, Jon Kuroyama, and Special Projects Engineer, Katsu Hibio, of HKS USA, installing the camshafts and properly breaking in the units, we began the second phase of testing. Equipped with a laptop and A/F meter to safely monitor engine conditions, the dyno was spun on a warm summer day with a significant increase of 257.0 hp and 249.6 lb-ft of torque. While the peak numbers seem minimal in gains when using these camshafts, a closer analysis reveals a consistent 10hp gain and amazing 20 lb-ft of torque increase over our baseline run from 2,000 rpm to 3400 rpm. The midrange power check resulted in the largest gains resulting in an increase of 14 hp and 18 lb-ft of torque from 4400 to 4600 rpm while a pickup of 15 hp and 20 lb-ft of torque was recorded at 6150 rpm. The HKS EVO IX MIVEC camshafts are sold as a set for a MSRP of $699 but can also be purchased as individual units for a MSRP of $380 each.
If it's true what they say that dyno numbers don't lie, then the proof is definitely in the pudding. Look towards the near future as we team up with HKS once again to conduct additional tests and deliver even larger horsepower numbers using the MIVEC camshafts, an HKS Valcon control unit and some fine tuning with the aid of a HKS F-Con fuel management system.