ACURA’S FIRST TURBO: WILL IT BOOST TUNER’S INTEREST?
Honda’s new hefty K-Series engine provides a performance boost for SUV consumers and could possibly offer insight into Honda’s engineering forecast. Developed specifically for the RDX, Acura’s compact sport-utility, the engine has been modified to accept the strain of a turbocharger; a brand first.
The major feature of the new system is a variable flow turbo (VFT), designed to regulate airflow with an actuator built within the turbo housing. Exhaust air is progressively directed into two main chambers, diverting air into the smaller chamber when air pressure is low, and throughout the entire system when air pressure is high. Controlled by the engine’s ECU, the computer determines the necessary level of flow to achieve efficient boost and desired power. Under these conditions, the impeller is able to spin quickly at low RPMs, eliminating relatively all turbo-lag and providing seamless force throughout the power band.
Similar attempts have been made by other manufacturers, but moving parts were often exposed to hot exhaust air, increasing repair costs and the frequency of failures. Honda’s straightforward technology places the inlet device in front of the turbine, insulated from the excessive heat, and thus substantially increasing durability.
The engine, named the K23A1, generates more torque than any other product Honda has sent to the United States, but thanks to the revolutionary i-VTEC technology the engine is respectably frugal. The potential for enthusiasts lies in the architecture, as it is closely related to the K-Series engines found in the RSX, TSX, and Civic Si. Engineers realized the additional burden they would be placing on the engine with the turbo, so the block was heavily reinforced, iron liners were added to cope with pressure and the crankshaft and connecting rods have been forged.
Due to this meaty reinforcement a direct engine swap is not possible. Nevertheless, this provides specialty equipment manufacturers with an opportunity to construct mounts and miscellaneous parts which will accommodate this engine. Given the popularity of engine swaps and the muscular structure of the K23A1, it is conceivable that enthusiasts will adopt this as their next project.
In the April, 2006 edition of Super Street magazine, they ranked the “Top Ten Engines” of the last decade in regard to the compact performance industry. Honda produced three from the list: B16/B18, D16, K20. The K-Series is the most current of the bunch and should continue to be a tuner favorite, especially now that it’s available in a turbocharged version.