Which is basically an upspec. Commodore. This one is VT, VX or VY - 1997-2003. I'm guessing, by the color and the way some of the parts in the engine bay are laid out, it'* a VX. Picture a fatter late '90'* Cadillac Catera (with an L67); the two look
very similar but, having seen an Opel Omega and VT side by side, they are actually significantly different. You guys would know this version as a 4-door version of the re-released Pontiac GTO - the GTO, or Monaro in Aust., was spun off the sedan platform. There are also wagon, utility and a long wheelbase (otherwise identical) luxury version: the Statesman. The transmission is the 4L60E. The L67 was only sold in the sedans, as far as I know. Auto. only with L67.
This is the second Commodore (actually only Calais and Statesman) body shape that the L67 was sold in. The first was the VS - sold between 1995 and 1997. This shape was smaller and about 120kg (260lbs) lighter. Consequently it was faster, even with all the luxury options. (Does that make two cars by GM with RWD L67'*)?
Parts of the chassis/floorpan of this earlier model date back to an Opel (GM Europe) derived car, first released in Australia, with local drivetrains, in 1978. (It'* a grandfather'* axe though; the body was significantly updated in 1988 - a "Top Hat" model update - and a completely new front suspension (1993) and IRS (1992) rear were introduced with intermediate models).
The later suspension designs were carried across fundamentally unchanged into the VT-VY shape ie. also the GTO, although there was an extra "toe control link" added to the rear supension around 2000, which the GTO should also have.
It is generally accepted that the L67 is as fast or faster than the Australian 5.0L V8 versions of the equivalent models but it was sold as a mid range engine option between the L36 and the V8. The performance was kept quiet by the marketing types and only sold in the heavier upspec. models. The LS1, introduced in 1998 or 1999, replacing the Aust. V8s (5.0L + 5.7L), was/is faster than the L67.
Yep, the */C housing, rather than just an adaptor, is different to the US models but what is basically the same car was sold in LHD form to markets in the Middle East. I don't know if the L67 was ever made available as an option there (definitely L36 and LS1) but a one off VT (about 199
version with an L67 was built by GM Australia (Holden) in LHD and used by an Australian car magazine to drive around Europe and the US and compare against the local cars. There might have been some coverage in Road and Track around that time as I still have a copies of the (Aust.) magazine articles and writers from Road and Track compared (briefly) the car with an L67 Grand Prix GTP and a Taurus SHO.
It might be interesting for you guys to look at the coolant pipe that you can just see to the left of the alternator in the picture (the bleed screw should make it obvious). That extends to the back of the engine and passes around behind the */C to connect with the thermostat housing under the pipe connecting TB-*/C. I think that the thermostat housing is specific to this model too. It is definitely an engine designed for FWD use converted to RWD. The installation is similar in this respect to the early versions of the Buick V6 sold in commodores.