GM V12

[RacerX]

.

[fl327]

hey youre from daly city, hey is the in and out burger open yet?

[grumpyvette]

heres the press release

 

GM Unveils V-12 and "Global V-8".(new engines from General Motors)(Brief Article)

Author/s: Lindsay Brooke

Issue: Sept, 2001

Innovative features give new engines power, economy and lower emissions.

 

GM has pulled the wraps off two new, highly sophisticated engines that will play key strategic roles for the automaker beginning in 2003.

 

The long-rumoured Northstar XV12 is a lightweight 7.5L dohc V-12, designed for future Cadillacs and possibly truck applications. Its purpose is to recapture the luxury-engine image crown GM'S flagship brand lost decades ago. And the so-called Global V-8, shown at this month's Frankfurt Auto Show, forms the basis of a high-volume engine family for applications in North America, Europe and Australia.

 

"Both are uncompromised, clean-sheet designs that take advantage of the latest piston-engine technologies," says Dr. Fritz Indra, head of advanced engineering at GM Powertrain. "They produce high levels of power and refinement, with greater fuel efficiency than our existing V-8s."

 

Speaking with Automotive Industries at the Monterey Historic races in California, Indra provided early details of both engines. While the Global V-8 is approved for production, the XV12 is still officially a prototype --though GM executives privately indicate it'll be built.

 

The ohv Global V-8 displaces 4.31, with output in the 300-hp range. It was developed for both transverse and longitudinal installations -- "maybe even Alfa Romeo," quips Indra. The all-aluminum engine features twin camshafts located near the top of the valley in the 75-degree cylinder block. Stacked one above the other, the camshafts operate three valves per cylinder (two intakes) via short pushrods. The set-up is reminiscent of the pushrod Mercedes-Benz Indy car V-8 developed with Ilmor and campaigned by Team Penske in the 1990s. In the Global V-8, the layout enables variable valve timing on both the intake and exhaust sides, which cannot be done on conventional ohv V-8s with a single camshaft.

 

"Another big advantage is up to 30 percent lower internal friction than a typical dohc engine," explains Indra. "This means greater fuel efficiency, particularly during idling and part-throttle operation." The engine also debuts an air-assisted gasoline direct-injection system, developed with partner Orbital Engine.

 

In North America, the Global V-8 is initially destined for GM'S Sigma platform, which includes the 2003 Cadillac STX (GMT265) crossover SUV; the 2004 Cadillac STS (GMT295) and 2005 Cadillac DTS and Buick LaCrosse (GMX271).

 

On a larger note, the Northstar XV12 was developed with partner Cosworth Engineering in the U.K. in a rapid nine months from concept to first running prototype. GM targets 750 hp and 450 pounds-feet of torque from the 60-degree V-12, putting it in a class beyond the current German, Italian and British (Aston) 12s. And it's a compact package, sized between GM'S Northstar V-8 and Vortec big-block V-8, and shorter in height than the small-block V-8. That's due to a linerless cylinder block, a nearly "square" bore and stroke (93 x 92 mm, with 100 mm bore centers), and a narrow 37-degree included valve angle. Indra says the engine weighs about 550 pounds without its Sachs 325A starter-alternator unit.

 

 

Continued from page 1

 

Early testing indicates the XV12, with its direct fuel injection, and ability to switch to 6-cylinder operation, beats the Vortec 8.11 V-8 in fuel efficiency. It's calibrated to run stoichiometric air/fuel ratios at 100-bar pressure until low-sulfur fuel becomes widely available for lean-bum operation.

 

"If we're serious about Cadillac, we need a V-12," asserts GM Vice-Chairman for Product Development Bob Lutz. "And we're very serious about Cadillac."

The Big Three from Detroit love to use the beautiful background of the Concours d'Elegance at Pebble Beach, California (and all of the activities surrounding the Monterey Historics), to debut concept cars and innovative drivetrains. Other than Chrysler's Crossfire and the Cadillac CTS, the only thing of note for performance fans was General Motors' innovative V-12 concept engine, called Northstar XV12. It displays several advanced technologies in a fuel efficient, V-8-like package.

 

This 60-degree, all-aluminum dual overhead cam (DOHC), four-valve engine displaces 7.5 L and produces 750 hp and 450 lb-ft, yet is the size of a V-B and is able to deliver excellent fuel economy.

 

"The Northstar XV12 provides a realistic look at what could power an assault on the high-end, premium automotive segment," said Fritz Indra, GM Powertrain executive director of advanced engineering. "At the same time it showcases a wealth of new technologies under development at GM Powertrain, many of which will eventually find their way into GM engines of all shapes and sizes."

 

The Northstar XV12 is the same length as GM's vortec 8100 V-8, and it has the approximate width and height as the Northstar 4.6 L and vortec 6000 V-8s.

 

"The packaging was probably the biggest challenge we faced, because from the outset we wanted to fit the V-12 inside the package of a V-8," said Steve Kowalk, GM Powertrain project manager for the Northstar XV12. "We focused on keeping the size down to fit as many different types of vehicles as possible."

 

Here are the highlights: Displacement on Demand, where cylinder shutdown is enabled through valve deactivation, which is performed by a compact switchable tappet (in all GM trucks and SUVs in 2004); Direct Injection Gasoline, using a multiple-injection setup, a single, high-pressure fuel injector located in each combustion chamber, spraying the fuel vertically down to the piston; Variable Cam Phasing, (helping to achieve 90 percent of its maximum torque at 1,500 rpm), using an internal exhaust gas recirculation (EGR) setup; a Variable Intake Manifold, with a three-stage variable induction system with tuned primary and secondary pipes for a flat torque curve; and Rear Chain Timing Drive, eliminating the need for a front engine accessory drive which reduces the engine's overall length. The engine appeared in GM's Cien concept car, but look for some (if not all) of these features in various engines on the GM line.

[Tim240z]

Wow...I want one BADDDDDD. I wonder if GM will consider doing some real life testing in a Z (mine of course)

Tim

[fl327]

nothing like a caddy, northstar, old school, whatever, they ride, like a caddy, mack daddy in the caddy with pants hella saggy. aw yeah.

i would like the pink v12 please.