Here comes LS3!

GENERAL Motors’ new "LS3" 6.2-litre V8 engine made its official debut in the Chevrolet Corvette coupe and convertible last week in the US, and is a strong candidate to be inserted into the Holden Special Vehicles (HSV) E-Series range in Australia during 2008.

It is unclear whether HSV would fit the LS3 mill as standard across the range, or use it to provide the performance differentiation it has sought for the range-topping GTS sedan.

Superseding the LS2 6.0-litre V8 in the Corvette, the LS3 produces 321kW of power at 5900rpm and 575Nm of torque at 4600rpm.

With a new dual-mode exhaust system specified, output increases to 325kW and 580Nm at the same rpm.

These are considerable improvements over the LS2, which in HSV’s VE Commodore-based range produces 307kW at 6000rpm and 550Nm at 4400rpm.

When combined with the revised six-speed paddle-shift automatic transmission (improved with new hardware and a new controller calibration that deliver quicker shifts), the LS3 can send the 1460kg Corvette to 60mp/h (97km/h) in a claimed 4.3 seconds.

HSV claims its LS2 cars – which are 300kg heavier than the Corvette – can accelerate from 0-100km/h in 4.96 seconds with the manual and 5.04 seconds with the auto.

Work was also carried out on the six-speed manual gearbox, which is claimed to have a more positive and direct feel during changes, with better gate-to-gate location. The final drive ratio for the manual is 3.42:1 (compared to the E-Series LS2’s 3.70:1) and 2.56:1 for the auto (compared to 3.27:1 in the HSVs).

The new small-block, pushrod-driven 6162cc V8 has a larger-bore cast-aluminium cylinder block (4.06-inch/103.25mm), high-flow LS7/L92-style cylinder heads, larger-diameter pistons, revised camshaft and camshaft timing, revised valvetrain with offset intake rocker arms, a high-flow intake manifold, high-flow fuel injectors from the Corvette Z06’s LS7 engine and a new engine cover.

GM has not yet released fuel consumption figures.

HSV this week refused to divulge when first E-Series upgrade will take place. A spokesperson said the company had a sufficient supply of LS2 engines for at least 12 months and that there were no plans for a powertrain upgrade "in the foreseeable future".

As for the Corvette, Queensland-based conversion outfit Performax International is working to have right-hand drive versions of the 2008 model available in Australia in the coming months.

However, general manager Nick Vandenberg told GoAuto this week that Performax was still to determine the extent to which the revised engine met Australian Design Rules and whether the 2008 Corvette could be added as a variant (rather than a new model) to its current program, which includes the current super-high-performance Z06 version – complete with the stonking (and unchanged) 377kW/637Nm LS7 7.0-litre V8.

Other changes to the Corvette series include minor steering modifications (aiming for improved feel), a unique split-spoke wheel design (for the 18-inch front and 19-inch rear wheels), new exterior colours, interior trim changes and an optional "leather-wrapped interior package".

A 2.73 performance axle ratio is also now available with the auto Corvette, when the Z51 package is specified.