Costing an additional $9990 above a 304kW SS or 340kW Clubsport and replacing the previous the W375 package, the W407 now gets – you guessed it – 407kW produced at 6250rpm in either Holden or HSV, which both also shift from 570Nm to 695Nm at 4950rpm.
Additions to the mighty LS3 include Walkinshaw Performance ceramic-coated headers, cold air intake, camshaft and valve spring upgrade and a dual-active catback exhaust.
Used vehicles with beyond 20,000km on the odometer also require new head gaskets, head bolts, and OEM lifters with lifter guides – which adds a further $1000 to the price.
Walkinshaw Performance tags the W407 as its “best naturally aspirated package to date.”
“Utilising a Walkinshaw Performance spec camshaft and associated componentry provides more top end power and torque whilst maintaining road handling manners for your daily drive,” it further explained in a release.
“In addition to the Walkinshaw Performance camshaft, the package makes use of a full stainless steel, stepped exhaust system, ceramic coated 4-into-1 long-tube headers and high flow catalytic converters, and an over-radiator cold air intake to gather greater volumes of airflow into the engine.
“This results in greater efficiencies in power and economy and is finished with all in-fill panels and shrouds keeping with the original equipment look of the vehicle.”
Rear badging, engine plaque and a certificate of authenticity are the only changes to the stock SS or Clubsport, although Walkinshaw Performance’s grey preview VFII SS also contained black badging with a brake upgrade, yellow callipers and HSV wheels with Continental tyres.
Walkinshaw Performance covers the Holden three-year/100,000km warranty for the engine, gearbox and differential – or the remainder thereof on used vehicles.