The shrieking power of Chevy's fastest-ever production Corvette is enough to get you into trouble before you hit third gear.

Introduced for 2006, the latest Corvette ZO6 is a performance tour de force, with a roaring 505 horsepower under the hood, plus the chassis, steering and brakes of an all-out race car. It's also a practical sports car that's docile in traffic and gets 26.miles per gallon on the highway, according to the EPA.

Loads of muscular torque and agile handling made ZO6 the perfect craft for a favorite five-mile stretch of Arizona blacktop: the steep, twisting segment of Arizona 89 that climbs the mountain just south of Yarnell. ZO6 charged through the turns with a thunderous roar, making short work of the challenging road.

The sixth generation of a remarkable 54-year production run, the latest 'Vette is clearly the best ever, and ZO6 is the top of the heap. Trimmer and more refined than the previous version, with an accommodating interior and more luggage space, the new Corvette represents real value compared with the pricey high-performance competition.

Of course, all this noisy fun should be taken in context: Nobody needs a 505-horsepower sports car. Of course, nobody needs a Prada handbag, an Armani suit or an Italian vacation, either.

But as they told me in Economics 101, the concept of "need" is pretty subjective while the concept of "want" is absolute. And there are plenty of hot-shoe drivers who really want a ZO6.

PERFORMANCE: The latest ZO6 ups the ante to 505 horsepower, 105 more than the standard Corvette. It will roar from zero to 60 in less than four seconds and hit a top speed of 198 miles per hour. The muscle is churned from a hand-assembled 7-liter V-8, a significant size for Corvette performance freaks because, in cubic inches, it famously measures 427. The engineers used advanced techniques and materials to achieve the power surge, with such tricks as titanium connecting rods and intake valves, race-bred airflow design and dry-sump oil system. The six-speed manual is the only transmission offered. The clutch is firm but not too heavy. The shifter was balky in the test car, no doubt the result of 8,000 miles of ham-fisted journalist test drivers.

DRIVABILITY: ZO6 hunkers down and goes where you point it, with flat, neutral cornering and seemingly limitless grip. Foot-wide rear tires help. The ride can get harsh over rough pavement, but the trade-off for the great handling is well worth it. Road noise and thump from those big tires can get annoying. Electronic stability control helps overly enthusiastic drivers stay on the road, but it's not so intrusive that it spoils the fun. ZO6 is lighter than the standard Corvette despite a heavier drive system. Credit a unique aluminum body structure combined with lightweight carbon- fiber components.

STYLING: ZO6 has several differing styling cues from the regular Corvette, including a wider front end, broader wheel flares and four large stainless-steel exhaust tips. A great look.

INTERIOR: Corvette's sophisticated cockpit is roomy and comfortable, with clear gauges and controls and decent luggage space under the rear-window hatch.

BOTTOM LINE: Starting off at $44,000, with the full-bore ZO6 priced at just more than $69,000, Corvette is the greatest sports-car performance bargain out there.

Vehicle type: Two-passenger, two-door coupe, rear-wheel drive. Engine: 7-liter V-8, 505 horsepower at 6,300 rpm, 470 pound-feet torque at 4,800 rpm. Transmission: Six-speed manual. Wheelbase: 105.7 inches. Overall length: 175.6 inches. Curb weight: 3,132 pounds. EPA rating: 16 city, 26 highway.

HIGHS: Awesome performance, roomy interior, value pricing. LOWS: Road noise, shifter woes, traffic-ticket bait.

Pricing Base price: $69,175. Price as tested: $77,425.

OPTIONS -Preferred package, including side-impact air bags; upgraded audio with seven Bose speakers, XM satellite radio and MP3 player; telescoping steering wheel with radio controls; heated seats; and luggage shade, $3,485. -Navigation system, $1,750. -Alloy wheels, $1,485. -One-year OnStar safety communications, $695. -Shipping, $825.