TOMALES, Calif. -- A particularly warped and winding section of California's Pacific Coast Highway north of San Francisco runs along the eastern side of Tomales Bay while passing through crossroads communities like Marconi and Hamlet on the way to Tomales.
Coursing over humpback hills and cutting acute-angled corners to chase the ragged shore, this twisty ribbon of asphalt seems like it was designed expressly to show off the sticky four-wheeling agility of a sporty new five-seat crossover SUV.
A trunk tag labels it as the RDX by Acura, marque of performance and luxury vehicles derived from Honda of Japan.
This new wagon, slotted for the compact class with a 104-inch wheelbase, totes Acura's first turbo-charged engine coupled to the spry wheel control of Acura's SH-AWD (Super-Handling All-Wheel-Drive) equipment plus high-tech gear for communications, navigation and entertainment.
The smart SH-AWD system can disburse the engine's considerable torque not only to wheels fore and aft but the left or right ones too. It's always engaged and enables the vehicle to maneuver on wet or dry pavement with the uncanny agility of a wily sports car.
The device goes further than AWD controls employed by other vehicles because it can automatically increase the rotation speed of an outboard rear wheel during quick and hard cornering maneuvers.
Boosting the rear wheel's rotation speed ends up decreasing the cornering load on the car's front wheels, which thwarts the tendency of an AWD system to understeer and ultimately enhances total tire grip through a turn.
It allows the RDX to carve precise turns on a curlicue road like the PCH and run circles around some size-wise competitors.
Acura's AWD system normally channels most of the engine's power to the front wheels.
At highway cruise speed, about 70 percent of the torque is driving the front wheels, while the remaining 30 percent goes to turn the rear ones.
If you put your foot hard into the accelerator, however, a computer quickly inverts the power ratio. It shoots 70 percent of torque to rear wheels to help the acceleration effort, while still holding 30 percent on the front wheels.
And there's plenty of power at play with RDX, thanks to the new turbo engine which pares the typical turbo's power lag by using a variable-flow turbo-charger.
The turbo 2.3-liter engine, from an aluminum block and in-line four-cylinder arrangement with micro-polished crankshaft journals, has Honda's advanced system of computer-controlled intelligence for regulating camshaft phasing labeled i-VTEC (intelligent variable value timing and lift electronic control).
It generates 240 hp at 6000 rpm plus torque of 260 lb-ft at 4500 rpm.
Sole transmission is a silky electronic automatic with five forward speeds plus Honda's Sequential SportShift override for clutch-less manual shifts with paddle tabs mounted behind the steering wheel's center spoke.
Based on a unit-body platform, the rigid structure of RDX shows the extensive use of high-tensile steel.
Also working in favor of a dynamic vehicle is the independent suspension -- tuned MacPherson struts up front and a multi-link design in back.
And there's a computer-managed vehicle stability control (VSC) system aboard, plus a four-wheel anti-lock braking system (ABS) with electronic brake distribution (EBD) and brake assist (BA) units.
The steering is crisp and true, stemming from a rack and pinion arrangement with torque-sensing and variable electric power boost.
And big 18-inch aluminum alloy wheels on the ground are capped by P235/55R18/99V high-performance all-season tires.
Take a walk-around tour of the RDX and you'll discover a streamlined body posing in hunkered stance that makes it appear ready to romp.
There's a low hood line to enhance forward visibility for the driver, with high-intensity discharge (HID) headlights mounted on front corners of the prow.
The front fascia shows a primary air portal to feed the engine radiator, with a top inlet serving as a cold-air duct for the turbo-charger's inter-cooler, which mounts horizontally above the engine.
On flanks the wavy panels feature bold and bulging wheel arches shoved toward the corners.
The roofline slinks rearward over a band of windows with black-capped pillars.
At the back a spoiler crowns the tailgate, which dips low to a flush bottom line against the bumper.
In the handsome cabin there's room for five riders with supportive bucket seats in front of a bench for three and a rear bay for cargo.
Acura's designers of the interior compartment describe the styling inspiration as an upscale urban loft apartment that's highly functional and laced with quality materials.
The driver-oriented cockpit features a leather-wrapped steering wheel, an instrument cluster with light-emitting-diode (LED) back-lighting for an easy read and a Multi-Information Display (MID) which provides access to a variety of electronic functions.
Posh gear includes perforated leather trimming the seats, automatic controls for the climate system with dual zones for comfort, power operation for windows and mirrors and door locks, the driver's bucket with eight-way power controls including adjustable lumbar support, heat elements inside both front buckets, a center console up front with briefcase-size locking bin, a power moonroof with tilt, auto-open/close, auto-reverse and key-off functions, a keyless entry device, the back bench with a 60/40 split-folding seatback and the Acura Premium Sound System with a six-disc changer, seven speakers and XM satellite radio service.
The Technology Package option installs a navigation system with voice recognition and rearview camera, AcuraLink satellite communication system with real-time traffic reports, the MID with steering wheel controls, a premium Acura/ELS surround sound audio system tied to a DVD-Audio changer and ten well-placed speakers, a Tire Pressure Monitoring System (TPMS), HandsFreeLink wireless telephone interface for Bluetooth-based mobile phones and a GPS-linked solar-sensing automatic climate control system with two zones.
2007 Acura RDX CUV MSRP is $32,995