General Motors Corp.

3.5L Twin Cam V-6 It seemed like we'd been hearing about the "Shortstar" forever. Rumors about General Motors Corp.'s modular DOHC V-6 derived from the famous Northstar 4.6L and Aurora 4L "Premium V" V-8s had powertrain watchers salivating at the prospect.

Last year's launch of the Shortstar - officially dubbed 3.5L Twin Cam - didn't disappoint. It instantly earned a position as one of Ward's 10 Best Engines for 1999, in its first year of eligibility.

The 3.5L Twin Cam V-6 stands above the mass of 3L V-6s in the market largely by virtue of another half-liter of displacement. GM engineers eschewed the now-common add-on gadgets like variable valve timing in favor of good old cubic inches - and with those cubes comes the virtue of long stroke.

Extending the range of the pistons in their bores produces fabulous torque, particularly in the middle-rpm ranges, making the 3.5L Twin Cam a most satisfying implement for squirting through city traffic and breaking out to beat that next ill-timed traffic light.

More stimulating, though, is the 3.5L Twin Cam's punch on the freeways and interstates. It lopes along at 75 mph (121 km/h), just below its real light-off rpm; further throttle provocation then summons a torque burst of profound influence - our 3.5L Twin Cam-motivated '01 Aurora test car displayed 75 mph-to-95 mph acceleration of heroic stature. And sustaining triple-digit speeds was the proverbial "walk in the park."

Yes. That long stroke yields the sensation of power reserves deeper than those of even the best 3L V-6s. It's a feeling of a uniquely "American" engine - the reassurance of generous displacement.

But there's also the unbreakable feel so prevalent in the Northstar and Aurora V-8s. The 3.5L Twin Cam exudes the sounds of fine inner workings, of tight tolerances and components dense where they need to be and finely optimized where they don't. The torque is intoxicating, but it's the typical GM fascination with detail refinement that delights.

The company's engineers pursued friction reduction with religious zeal. They specified practically everything you would if you were designing your own V-6: powder metal connecting rods, a forged crank, roller-finger cam followers. A chain cam drive that never needs adjustment or replacement. And the amazing and now-legendary "limp home" feature that allows this all-aluminum engine to operate without any coolant without fear of meltdown.

In short, the 3.5L Twin Cam has been developed to the high standard we know GM Powertrain sets when it gets serious about an all-new anything. It doubtless is not a cheap engine - in fact, to watch one built component-by-component, it looks positively lavish - yet now comes standard in the modestly priced Intrigue and will be the base engine for the '01 Aurora starting this spring.

Probably nowhere else can you buy so much engine excellence at such reasonable cost.