Engines … the LS family of V8’s
Thinking of building an off road racer … then the powerplant is where you need to start with the chassis, and looking at most Ultra 4 trucks and desert racers you will not go far wrong by checking out the General Motors LS range of V8 lumps.
When it comes to V8 engines, petrol-heads the world over appreciate this type of motor for its fairly compact layout, tremendous performance, and of course the noise it produces. Despite the industry’s tendency to go green, the passion towards the V8 is still stronger than ever.
The first engine to be built in a V8 configuration started life as a patent in 1902. First produced in 1904, the so-called Antoinette V8 was installed in various aircraft and speedboats. A year after the first ever V8 engine came into the world, Rolls Royce developed a 3,535 cc 216 cu.in. V8 motor. Only three cars were equipped with this eight-cylinder lump before the British luxury manufacturer reverted back to a straight 6 design.
Introduced in 1914, Cadillac was the first automaker to mass-produce the V8 engine. This engine configuration steadily grew in popularity through to the 1950’s in the U.S. until finally reaching its peak in the 1970’s, just before the oil crisis hit the world.
From all the V8s that were bestowed upon us over the years, some of the most important designs come in the form of the GM LS Generation III and IV small-block V8 engines. It might have started life as a clean sheet design, but the creators of the GM LS engine family didn’t ignore the historical importance and timeless appeal of the classic small-block V8. General Motors introduced the LS series in the then-new 1997 Corvette. Known as the LS1 small-block V8, this motor eventually replaced the LT1 small-block V8 of the Chevrolet Camaro. Whereas these go-faster machines were animated by the aluminum version of the LS1, trucks and SUVs used the iron-block version of the motor. Similar to the previous generation small-block V8, the LS1 eight cylinder mill displaced 5.7 litres.
Even though there are some significant differences between the Gen III and Gen IV, all LS family engines share some common features. These include the 4.40-inch bore centers (similar to the original Chevrolet small-block V8), six-bolt cross-bolted main bearing caps, a center main thrust bearing, 9.24-inch deck height, 4-bolt per cylinder head bolt pattern, 0.842-inch lifter bores, as well as a distributor-less coil-near-plug ignition system.
The LS family could have been replaced by the Gen V LT in 2013, yet the LS soldiers on in several US spec pickup trucks. Because the Gen IV LS is nearing the end of its career, we feel the time is right to name the bread winners for GM from the 30+ different versions of LS V8 engines.
LS1 and LS6
The LS1 was produced between the 1997 and 2004 as a 5.7-liter (346 cu.in.) V8. 2001 saw the introduction of the LS6 in the Corvette Z06, until its demise in 2005. Whereas the LS1 and LS6 share the 5.7-liter displacement, the LS6 engine differs from the LS1 V8 with a much stronger block, improved bay-to-bay breathing, and more capable heads, intake manifolds, and camshaft.
It was 2005 when the Gen IV design debuted with the 6 ltr (364 cu.in.) LS2 V8 engine. The LS2’s larger displacement came with a greater output compared to the LS1. In terms of interchangeability, the LS1, LS6, LS3, and L92 cylinder heads work well on the LS2 motor.
LS3 and L99
The LS3 announced the era of unprecedented performance for the Chevrolet Corvette. First seen in 2008, it
brought 430 horsepower to the table from 6.2-liter (376 cu.in.) displacement. At the time, the LS3 was the most powerful base Corvette engine ever. Boasting larger bores than the LS2.
As for the L99, this is a fuel-efficient variant and its selling point is the Active Fuel Management cylinder deactivation system.
Commonly labeled as the most intriguing engine of the LS family, the LS4 is a 5.3-liter lump that equipped some front-wheel drive models in the states. The 303 horsepower LS4 features a transverse mounting position, which spoils everything that’s good about this engine.
The legendary LS7 was the focus point of the sixth-generation Chevrolet Corvette Z06. Its 7-liter (427 cu.in.) displacement made it the largest LS offered in a production vehicle. To cope with the 4.125-inch bores, engineers gave the LS7 a Siamese-bore cylinder block design. Hand-built at the GM Performance Build Center in Wixom, Michigan, the LS7 V8 blunderbuss was good for 505 horsepower when it was new thanks to go-faster components, such as competition-proven heads, titanium rods, and titanium intake valves.
Before the Gen V LT4 and its 650 all-American horsepower, the LS9 claimed the title of most powerful production engine made by General Motors. The 6.2-liter supercharged and charge-cooled motor powered the Corvette ZR1 with 638 horsepower. Components that made this output possible include a 2.3-liter Roots-type supercharger, dry-sump lubrication, and roto-cast cylinder heads.
The LSA variant is simply put a detuned LS9 motor with all the good bits removed or scaled down to suit its required installations.
The LS range has continued to be constantly in demand with a strong supporting fan base, unfortunately one day the plugs will be pulled either through emission standards or fuel consumption. When that day comes who knows where the uprising will start.
However, for some of us, the heavy oil burning smokers will remain kings of the power houses, we always get there in the end …
Text extract credits; autoevolution.com