$20m and fuel economy price for Holden VFII

Holden spent around $20 million on developing the Commodore VFII. In global automotive terms that’s a paltry figure, but there’s no doubt the car that’s rolled out achieves maximum bang for buck.

That’s because the focus was on performance, the area of Commodore sales that has really held up in recent years as the large car segment lost its pre-eminent position in the Australian new car market. Commodore sports models now account for more than 50 per cent of total volume and V8s a 30 per cent slice by themselves.

So with this being the last hurrah for the locally-developed and built Commodore before the Elizabeth factory shuts in 2017 (apart from some still secret farewell editions), the decision was made to upgrade from the 6.0-litre Gen IV to the 6.2-litre LS3 across the V8 range. Capacity is up, power is up, torque is up and so is fuel consumption - by up to 12 per cent. In this politically correct age that doesn’t read quite right.

“It’s certainly not a conscious ‘we don’t care about fuel economy statement’ from Holden,” chief engineer Andrew Holmes told motoring.com.au.

“What we care about what customers want.

“We make very fuel efficient V6 engines and that’s what customers want. We make V8 engines and customers are saying ‘we want more, give us more, that is what we are interested in, old school muscle, give us more’,” Holmes stated.

“In the end that is what we are here for… We listen to our customers, that’s what they have asked for and that’s what they have got. That’s basically where it starts and ends,” he said.

Moving to the LS3 was a logical decision because Holden has experience fitting it into the Zeta-based Commodore (VE, VF) derivatives dating back to the Pontiac G8. That car has more recently morphed into the Chevrolet SS. That other slightly more famous Chevy, the Corvette, also runs the LS3.

“We knew we were going to use this engine a long time ago,” said Holmes.

Of course, Holden Special Vehicles has also used the LS3, although it has just upgraded to the supercharged LSA V8 across most of its range to keep one performance step ahead of Holden.

The Holden version of the LS3 makes 304kW and 570Nm, as either a six-speed manual or six-speed auto. That compares to the Gen IV’s 270kW/530Nm as a manual and 260kW/517Nm as an AFM (Active Fuel Management) auto known as L77.

That figure still falls shy of HSV’s claims, partly because the performance tuner works in the more optimistic DIN rating (Holden uses ECE), but also because HSV fits extractors, a level of tweaking impossible on the Elizabeth line.

Holden claims a 4.9 sec 0-100km/h and 13.0 sec 0-400m time for a manual LS3 Commodore running on 98 RON (the engine will cop 91 but likes 95 RON minimum). Add one tenth for the auto.

But it’s not only extra grunt available over a wider range that delivers that cut in time of around 0.5 sec compared to the Gen IV. Shorter final drive gearing for both manual (3.45 to 3.73:1) and auto (2.92 to 3.27:1) helps, as does the LS3’s ability to rev out to 6600rpm before the electronic limiter kicks in. The Gen IV, by contrast, ran out of steam at 6000rpm.

While achieving 300kW-plus was critical for Holden, so was extracting the right sound from the package. Feedback from customers was they wanted more noise as well as more go.

“We worked really hard on this and we wanted to develop a unique sound character for the car,” explained lead development engineer, Amelinda Watt.

“We did a lot of benchmarking at the start. How do other people do this? How do they get sound into the car? How do their exhaust systems work? We listened to an AMG, all sorts of things across the range, and then tried to work out what works best for Commodore,” she explained.

“VF was a huge step forward in refinement so at no point did we want to compromise that.”

The solution Watt and her team arrived at was twofold; a bi-modal exhaust at one end (Holden’s own design not HSV’s) and a sound tube piping induction noise into the cabin at the other.

One critical feature of the bi-modal exhaust system is the Baillie Tip, which consists of a unique opening in the exhaust that reverberates sound back through the system towards the cabin, increasing the overall sound level up to 10 per cent.

The tip was developed by and named after Holden engineer, Dr David Baillie, who died earlier this year of leukemia.

“The Baillie Tip is a very smart but simple piece of engineering that contributes to the overall vehicle beautifully,” said Holmes.

“Naming the part after him was a non-negotiable tribute that all the Holden engineers wanted to do.”

The Baillie Tip alone accounts for an extra three decibels of cabin volume, while overall the various measures increase interior sound level by 10 dba – or double the old car. The bi-modal exhaust activates based on a combination of throttle pedal position, revs and gear selection.

All short wheelbase V8 models get both the bi-modal exhaust and the sound tube, but the Caprice misses out because of its limo-orientation. It does get a retuned passive exhaust.

The VFII sports models are the only V8s to get vents on the upper bonnet to expel heat, a lower grille size enlarged by six per cent to allow more cooling air and new fascia inlets to cool the brakes and negate the extra drag created by the larger opening. Wind tunnel work was completed at Monash University in Melbourne.

All this is really designed for the SSV Redline flagship performance model which Holden wanted to ensure was track capable. That’s why the Calais and Caprice V8s don’t get more air flow or the vents. Its also why the Redline remains the only model to have Brembo brakes, which now include four-piston rear calipers as well as the fronts.

Lesser V8s stay with the old VF brake package, or can upgrade to a new option, the single piston and 345mm disc front-end set-up developed for the Chevrolet PPV police vehicle.

Going to fixed caliper four piston rear Brembos has also enabled Holden to retune the Redline’s FE3 suspension tune, moving the rear stabiliser bar mount 250mm outboard and reducing its diameter from 28mm to 25mm. Combined with a reduction in rear spring rate from 60N/mm to 55N/mm and retuned dampers, Holden is claiming better ride with no reduction in handling quality.

Holden started the VFII program “in anger” around mid 2013 and completed 250,000km of test kilometres at its Lang Lang facility and on public roads, including the Alpine region, the Great Ocean Road and 100 flat-out laps at the Phillip Island Grand Prix Circuit.

Clearly, such a focused development program with such a limited budget means much rolls on unchanged from the VF into VFII: the look of non-sports models apart from some badging and wheels; the V6 engines; transmissions; the FE1 and FE2 suspension settings; and the interiors of all the cars.

But in the minds of the Holden engineers who worked on VFII, turning out a 300kW-plus V8 sports sedan isn’t a bad job to focus on.

“We are pretty proud of it,” said technical integration engineer Dan Pinnuck.

“Everyone had one goal and that was to make this car the best it could be, because a lot of us would buy this car.

“From the get-go everyone was all heading in the one direction to make the best Zeta-based Commodore we could,” he said.