Saturday, 18 June 2011

Northstar’s Greatest Hits: Taking a look at GM’s now-departed V8

When the last Cadillac DTS rolled out the factory doors at General Motors’ Detroit/Hamtramck Assembly Plant this week, it took with it both the historic de Ville nameplate and the division’s once-promising Northstar V8 architecture.

One of the world’s most advanced – and most-hyped – engines when it debuted in the 1993 Cadillac Allanté, the Northstar would go on to power nearly all of Cadillac’s premium sedans, as well as a host of other GM products.

The Northstar was designed to replace Cadillac’s mediocre V8 lineup with a single dual overhead cam unit that GM hoped would have more success taking on increasingly-advanced European rivals, like BMW and Mercedes-Benz, not to mention then-newcomer Lexus. As history tells us, GM didn’t quite hit the mark – but that doesn’t mean the Northstar isn’t to be celebrated.

Northstar combined a cast-aluminum 90 degree block with cast-aluminum pistons with valve clearance for a non-interference engine. With four valves per cylinder, distributorless ignition with a waste spark setup and such features as 25 degree intake valves and a cam-drive chain case, the engine wasn’t short on technical highlights.

It initially mated to a 4T80 four-speed automatic transmission, the Northstar was later bolted up to a six-speed automatic for certain applications. Fittingly, the last Northstar vehicle, a Cadillac DTS, still featured the 4T80.

Cadillac initially billed its range of advanced technologies (Bosch ABS, automatic-adjusting shocks and Magnasteer hydraulic power steering) as part of its Northstar System, although that grouping was more marketing than anything else.

Looking back
The Northstar hardly makes our top 10 greatest engines list, but it certainly made its way around the GM offices. Variations of the Northstar engine found their way under the hoods of more than just Cadillacs as GM sought to capitalize on its costly development – over its nearly 20-year lifespan, it was used in Buicks, Cadillacs, Oldsmobiles, Pontiacs and even a Shelby.

Let’s take a trip down Memory Lane to revisit some of the Northstar’s more interesting engine bays – not all of which exactly qualify as Platinum, but they’d at least be on its Greatest Hits album.

Debuting in the Cadillac Allanté, Cadillac’s laughably costly Italian-penned roadster, the Northstar first arrived in GM’s most avant-garde model. But the Allanté was already pretty old by 1993 when the Northstar hit the scene. This model lasted for just one year, when a mere 4,670 were built in both Italy (where the bodies were made by Pininfarina) and Detroit (where assembly was completed after the bodies were shipped over in a purpose-made 747).

Perhaps its greatest moment is when Hollywood chucked one out of an airplane in Terminal Velocity. The Allanté’s story is a glimpse into the grossly out-of-touch complexity of GM in the 1990s.

From there, the Northstar took a turn for the mainstream with the introduction of the notably more modern range of Sevilles – the STS and SLS. Despite its front-wheel-drive architecture, the STS was supposed to square off against the BMW 5-Series, Mercedes-Benz 300E and the Lexus LS 400. By most accounts, it really was an excellent car – just not quite up to its rivals’ driving dynamics given its drivetrain that pulled instead of pushed.

The STS was the top pick of the group since it offered a then-astounding 295 horsepower and 275 lb-ft. of torque. If only it went to the right wheels.

Like the Allanté, the STS actually debuted with the wrong powertrain – the 1992 version came with a decade-old weak 200 horsepower 4.9-liter.

GM’s Oldsmobile division did things right, for the most part, when it decided to reinvent itself with its shapely Aurora. Although still front-wheel-drive and compromised by some peculiar packaging (like a rear window that distorted the view out the rearview mirror), the sedan was positively sexy.

The Aurora didn’t get the 4.6-liter version of the Northstar used in its Cadillac cousins. Instead, the Oldsmobile division was granted a 4.0-liter version codenamed L47, which put out a still-decent 250 horsepower. Since Oldsmobile was a major supporter of the Indy Racing League, its IndyCars used a 650 pony racing version. Meanwhile, Shelby popped its own version of the 4.0 in its Series 1. Ironically, after GM pulled the plug on Oldsmobile, Cadillac’s Le Mans Prototype racing division got access to a twin-turbo version of the Oldsmobile IRL engine.

After the reasonably successful first-generation Aurora, GM’s already-neutered Oldsmobile division laid down a bunt with its 2001 remake.

But by then, Oldsmobile had already expanded the Northstar family even further with a V6 version dubbed “Shortstar” by insiders. Displacing 3.5 liters, the 90 degree V6 wasn’t really just a shortened version of the bigger V8 since it had its own unique block engineered from day one. Used in the Oldsmobile Intrigue, the Shortstar was smooth, sonorous, and incredibly expensive to build. It died with Oldsmobile in 2002 in favor of the High Feature V6s used in midsize GM sedans and crossovers today.

When Bob Lutz found himself at the helm of GM’s products in the early 2000s, he fast tracked quick changes to help save some of the automaker’s divisions. Oldsmobile’s death was imminent, but Lutz tried to stave of Pontiac’s with the 2004 Bonneville GXP. Free of goofy cladding, the Bonny had decent performance credentials – like a 275-horsepower Northstar – but it didn’t have the chassis dynamics to match. It lasted just two years, when the similar Buick Lucerne CXS (later Super) took over with a more bargain basement luxury-oriented package.

Cadillac’s early 2000s renaissance wasn’t just from its smaller CTS, which didn’t use any iteration of the Northstar. Although only the CTS was a sales success, Cadillac in 2004 turned the V8 to create a longitudinal version for its SRX tall-wagon crossover, Corvette-based XLR roadster and, finally, its third-generation STS.

None of the three were big hits with consumers, but each is interesting on its own. The SRX and STS shared GM’s then-new Sigma architecture with the CTS, which gave them solid rear-wheel-drive handling. Neither was a paragon of interior sophistication initially, although a later update made the SRX feel worth the coin. But consumers never caught on and the SRX went front-wheel-drive last year, while the STS died off earlier this month.

The XLR was the biggest flop of the group, but both it and the STS spawned the ultimate Northstars: The XLR-V and STS-V. A supercharged 4.4-liter version of the Northstar gave these two short-lived (2006-2009) models up to 469 horsepower (XLR-V) – a gargantuan jump over the original 1992 V8.

The Northstar was never meant to be a performance engine, so by the 2010 model year, GM was selling only two Northstar-powered Cadillacs, the DTS and STS, and one Buick, the Lucerne Super. All three died this spring at GM’s Hamtramck plant so that GM can build eco-friendly Chevrolet Volt and the upcoming four-cylinder-only Chevrolet Malibu.

Rest in peace, Northstar.


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