Front Wheel Drive LS V8: Looking Back on the GM's LS4 Experiment of the Mid 2000s
During the last 20+ years of the American auto industry, no engine has made the kind of impact that GM's LS series small block V8s have. We all know the aftermarket and swap potential of these engines have no limits, and during its production run GM used variants the LS engine in all sorts of vehicles.
Starting with the C5 Corvette in 1997, LS motors found their way under the hood of everything from muscle cars and Australian imports to AWD SUVs. The most unusual application of the LS V8 though may have been in a trio of vehicles GM sold in the mid 2000s. This is the story of the time the LS V8 went front wheel drive, resulting in some of the most unique American performance cars of the decade.
Of course GM's history with front wheel drive V8s goes back well before the LS4. Back to to the Oldsmobile Toronado and Cadillac Eldorado of the 1960s and on through the Northstar V8s of the early '90s, but there's something especially interesting about seeing the traditional OHV small block being used in FWD applications.
Dubbed the LS4, the front-drive version of the LS V8 displaced 5.3 liters, but unlike the 5.3 liter V8 used in GM trucks it featured an aluminum block along with cylinder heads shared with the LS6. It made 303 horsepower and 323 pound feet of torque. Just for comparison's sake, the current king of FWD power rankings, the Honda Civic Type R makes 306 horsepower and 295 pound feet of torque from its turbocharged four cylinder.
In order to get the small block to work with in a transverse, front-drive setup the LS4 used a shorter crankshaft and the starter motor was moved from its traditional location. The LS4 came mated exclusively to a four-speed automatic transmission and featured displacement on demand for improved fuel economy.
Over the course of its run the LS4 was offered in four different GM vehicles, and perhaps the most well known of the group was the 2006-2009 Chevy Impala SS. Not be confused with Caprice-based Impala SS of the 1990s, the 2006 version was basically a rental car with a V8 under the hood—and that actually makes it pretty cool.
While it may not have been a true sports sedan that would scare off BMWs, the FWD V8 Impala SS was powerful cruiser capable of hitting 60 miles per hour in the mid-five second range and running a low 14-second quarter mile.
Compared to the aggressive, swoopy looks of modern sedans the mid 2000s Impala SS looks pretty plain, but in a way that actually goes in its favor as few will suspect it has an LS V8 under the hood.
In addition to the Impala SS sedan, the LS4 could also be had in the two-door Monte Carlo SS. At the time the Camaro was on hiatus from Chevy's lineup, so for Chevy loyalists a V8 Monte Carlo SS was about as close as they could get.
They may have been front-drive mainstream cars, but the option of V8 also helped bit a little stronger connection between the road-going Monte Carlo and Impala and their NASCAR counterparts of the era, even if the race cars were just decorated body shells over a tube chassis.
However the most enthusiast-oriented of the LS4 cars came from Pontiac, who dropped into the small block into its Grand Prix sedan for the rare GXP model. What made the Grand Prix GXP stand apart wasn't just its horsepower, but also the lengths its engineers went to improve the car's dynamics.
The biggest obstacles when having a 5.3 liter V8 driving the front wheels are both torque steer and understeer, and the GXP's engineers applied to some unique tricks to help mitigate this. The big trick was going to a "reverse' staggered wheel and tire setup with 255-width tires up front and 225-width tires in the rear. While the tweaks didn't quite turn the Grand GXP into a world-beating sports sedan, it was a surprisingly well-rounded machine for being a front-drive, V8-powered anomaly. It even included Bilstein suspension for further-improved handling.
Last but not least, the LS4 was also offered in the luxury-oriented Buick LaCrosse Super for the 2008 and 2009 model years, and with the V8 under the hood the LaCrosse Super was one of the quickest Buicks since the Grand National of the 1980s.
While all of these V8-powered sports sedans and coupes never sold in larger numbers, they certainly provided a unique sort of motoring experience and if you can find one for sale today they should be pretty cheap. Nobody will suggest that a FWD machine is the ideal application for a small block V8, but if you are looking for a quick, comfortable and unique daily driver there's a lot to like here.
Whether you consider them underrated enthusiast machines or just interesting footnotes of modern automotive history, it's likely the the fall-off of sedan sales and the move to small displacement turbo engines have guaranteed the FWD V8 sedan experiment won't be repeated again.
Speaking of unusual LS-powered oddities? Have you forgotten about the Saab 9-7X Aero? We almost did.