Zeta II - The More Things Change.....
A Technical Preview of GM's Global RWD platform
May 29, 2011
By Mark Cadle
So having looked at the thinking that created Zeta , how will Zeta II be different? Now that we know it is not to feature as a product base on any other continent (apart from the existing export markets and North America) we can say with some certainty what it will be.
Zeta I is a very competitive chassis offering on cost, performance and crash-rating, plus included safety content. Zeta II's mission will be to meet or exceed these credentials while lowering mass, build costs and improving dynamics.
The GFC taught Holden that the old adage from the days of the Button Plan, 'Export or Perish', is not entirely correct; and not the only thing to consider in terms of surviving. Holden was caught out by events beyond it's control - working extremely hard to build up it’s export market to America for the G8 sedan; only to have it vapourise! Just before the GFC hit, sales were starting to gain traction and actually edging up month by month as awareness of the car increased - unusual for GM product, getting stronger as time went by.
Improving the right mix of models with a certified-smash GXP (reduced numbers after the Pontiac Obituary announcement basically sold out in seconds flat); plus the stillborn 2010 models which were to introduce the 300hp SIDI V6, aero-aids to aid fuel savings, the Holden iQ touchscreen with native Navigation for the US would have gong a long way to answering the criticisms of the V6 and lack of features.
One of Zeta's strong features is a highly-automated factory with resulting low production cost. This will remain.
Then came the GFC, which we don’t need to revisit. Suffice to say, Holden like everyone was hurting – the Middle East market vanished overnight. Holden’s CEO Mike Devereux was in Charge of GM Saudi Arabia then. He told me all you could see was a sea of unsold, shiny GM cars, SUVs, Escalades, STSs, Chev Luminas with more arriving by ship all the time – and no buyers. No ‘ET phone home’ to cancel orders – they’re building them to send on out. That’s when it isn’t a good time to have a key to the Executive Washroom.
Another major thing the cancellation of the G8 project taught Holden was not to allow yourself to be at the mercy of external factors: in future Holden will target exports as they present themselves: if they don't, Holden can build either of it's two bestselling models in whatever proportions to keep business and the factory ticking over. And cherry-pick any opportunities for high-value builds (V8 RWD sports or luxury or police sedan in short or long wheelbase). No-one else in the GM world is going to do this - so Holden may as well set themselves up as the default RWD supplier.
2-door coupe off VF? Not without significant potential exports.
VF is likely to appear in the Holden product portfolio in RWD form only (SUV roles going to the Captiva and the, new, large SUV GM is developing off the next-gen Colorado for Australian market vehicles) we will again see a short sedan, long sedan (Caprice), Sportswagon and a Ute, which at this stage is likely to be the only 2 door variant. You'd never say never to another Monaro or AWD variant off Zeta II totally, but it's unlikely.
How Will the VF Commodore Change?
The answer is, not in major significance on outward appearance. It will retain largely it’s proportions (which is the biggest interior that will fit into a RWD 200" sedan) and basic styling, probably with more elements of Volt, Cruze, Malibu featurings, like the sculptured bonnet/boot sides. It won't get faddish styling that hurts practicality like 4-door coupe rooflines, or block-of-flats frontal styling (Dodge Charger, looking at you!).
This is partly because the design in Australia has been a winner since Day 1 - against the odds it’s still until recently won the sales war against all comers. Even after five years the market seems to like it’s shape; all we’ve had is a minor Series II update which has kept it moving. Changes to powertrains are more important. SIDI engines and the 6L50 transmission were important improvements.
It’s price/performance/features packaging in the various versions is mostly spot-on for the market they sell in – the Ute, Sportswagon and HSV versions are still waltzing out the door comparatively. It’s just changing societal tastes, plus fuel costs that are leading a drive to small-medium SUVs. But like BOF trucks in the US, Commodore business is good business in Australia, because it’s high-profit margin – and the sales are dropping at the cheap Executive and family-entry end, but holding up well at the luxury, sport and V8 end of the market.
Will the Champ back it up in 2013?
If it does win the best-seller title again it will be a miracle, as the market for large cars is nosing down steeply – the Camry/Aurion and Falcon have declined massively in sales to a fraction of their former volume. Commodore including commercials and LWB cars sold around 90,000 vehicles annually ten years back – now it’s looking like the 60,000 mark.
Times They Are a'Changin'
This is going to make a major difference to the Commodore in the future - the humble Cruze.
Holden can build Commodores, or they can build Cruzes - what people are buying will determine build proportions. Eventually, Cruze will most likely overtake Commodore volume.
Fuel prices are biting. Families are downsizing, often to one adult and one or two kids. There's more single person families, no-kids families than ever. In the era of the $100 interstate airfare, and time-poor modern lives, people don't drive as far - certainly not interstate or holidays overnight as much; like used to be common even ten years back.
Plus a shift in perceptions: 'action' vehicles like SUVs are trendy and fashionable - even if the majority are 2WD, often based on boring sedans underneath. All these things are contributing to the gradual decline of the traditional Aussie six that was a mainstay of the family for decades.
Then there were personal taxation changes in 2007, raising the marginal tax threshold. These reduced the taxation incentive for people to salary-sacrifice for leased motor vehicles. Cars like the XR6 Falcon and SV6 Commodore exist primarily for this market. If you take out the loss of sales volume of these and base 3.0 litre Commodores, it's little wonder that V8s make up a staggering 40% of sedan/wagon, and 70% of Ute sales; never the case prior to 2008. People paying their own, post-tax dollars for cars are making different choices: an Australian-made car with subsidised purchase, fuel and running costs that most fleet deals effectively provided was very tempting.
Sooner or later we will have a carbon tax which will effect motoring. That and government/corporate pledges to be 'green' has meant many business buyers have mandated four cylinders, and governments Aussie fours. Hence the local assembly of Cruze, and the importation of the Malibu: which will give Holden strong contenders at that level. Over time these will subsume probably the role of Omega Commodores. That's bad for volume, but the factory is now flexible enough to substitute Cruze production on a sliding basis. As more models of Cruze (hatch, wagon) come online production will increase.
What does this mean: well, firstly and probably inevitably Commodore will cede the No 1 seller plate (hopefully to Cruze). And the Cruze will take over the running in the lower-margin, volume fleet and economy market level along with the Malibu. Over time I wouldn't be surprised to see the Omega model disappear.
That isn't bad news for Commodore: on the contrary, it allows Holden to position it as a more premium offering, which should increase it's appeal as an exotic overseas. With the new updated SIDI 3.6 and Gen IV V8s coming: plus a prospective move back to America in little more than twelve months, we should see a less-utilitarian and slightly more upspec basic product.
Efficiency improvements will make it all-around more appealing; performance, economy and general driving dynamics should all improve. It can be made a little better equipped and more luxurious at all trims, because it can be set up to be a higher-margin vehicle. Styling will move the language along from both the TT36 and VE Commodore shape. It will incorporate some corporate elements from other models - uniquely married to Holden's own grille and design lanuage.
More than Skin Deep
But there will be much under the skin that is different. The major, major difference, and what should create a major change to weight and construction is layer build.
Ignore styling: styling is a moveable feast that can be stuck on any platform: the Cadillac XTS is the best example of this: Along with a Lucerne-ish roofline, it wears Art & Science styling originally intended for the Zeta DTS car. Of course, budget for the XTS as a stopgap (and probably eventual transformation into the Lucerne it was probably developed as) means the roofline misses the Z-profile 80’s Seville profile of the Zeta ULS sedan.
Volt (Delta II - shared with Cruze) layer-build front and rear chassis modules. Note the relative simplicity compared to Zeta I, below. Lighter weight vehicle, but starkly uncomplicated.
Because Zeta 1 marries long single members into the cabin understructure, they are large to avoid bending under stress – hitting a pothole at one end of the car, or full-throttle application in a low gear wants to twist the chassis diagonally. Hitting a speed hump or road-join tries to make the whole car bend across the middle.
Any welder will tell you – joining long pieces with welds, even spot welds, distorts them the further along you go and introduces stresses if you try to resist them moving. The other issue is, with such long pieces, access for the auto-bots is slow and awkward due to a limited reach and movements range. Both these things means slow fabrication times and special care needed to produce a properly-married set of modules. The weld pattern is critical, and the size and shape and thickness of the steel gauge of some elements is compromised to some degree to compensate for access limiting the placement of the welds. It’s not a terrible thing, as Zeta 1 is more than capable: but able to be improved on. You end up with a structure that is tough – just not light for it’s size.
Zeta 1 shell: a long reach for the auto-welders is needed to complete this from stem-stern. Doable, but layer-build should allow more efficiency.
You can think of modular build like a Mechano-set – you build things with long exterior segments joined at corners with gussets and cross members. So everything builds off the main ‘bones’ which in Zeta’s case are the long horns of the front and rear modules which are effectively welded into similar structures in the floor pressing, closed off by the ribs. The passenger cell is sort of perched on these rather than part of them. These do not lack strength, but have to be fairly hefty to avoid bending along their length. Getting access to weld them properly in assembly is hard. And their very size makes it trickier to maintain strength and a realistic weld pattern.
Zeta II, on the other hand, adds Layer Build to the mix. Layer build is more akin to building a house from a deck of cards: small compartment sections that interlock to provide more strength than any of the relatively small-section bits. So you build a small section, build another piece off it, another piece off that, then another, then another etc.
Think of it like the Corvette ZR1's bonded honeycombed-aluminium, balsawood-core chassis. The strength to handle 600+hp comes from the thin aluminium sandwiched around balsa wood, a material not known for toughness or torsional rigidity of itself. The balsa maintains the proportions of the aluminium, and in those spatial relationships the alumnium is more resistant to bend than heavier gauge steel in a solid sheet.
Simple playing cards can support surprising weight when arranged in this way. Layer build produces multiple, small, closed-compartments to build strength-on-strength. Also like honeycomb.
Volt (Delta II) front chassis module pressing. Unassembled, it's a simple 3-sided channel pressing of no particular strength. Welded to the floorpan, it becomes an enclosed spar member of much greater strength.
Volt front wheel/suspension housing - the element is built from fabricated sheet sections where inner welds are performed, then sealed by outer sections. In this case, the upper front guard (still to be added) seals this chassis member to the A-pillar root, and produces a strong irregular-sided box section that forms one contiguous structure. This is a crash load-path, a weight-bearer and outer skin all in one.
The Biggest Loser - Jenny Craig Time
A prime target of VF will be fuel efficiency. Along with improved aerodynamics, Holden has announced with the aid of a government grant the introduction of aluminium panel technology. The strength of Zeta I's arrangement was detailed in the previous Zeta article. This should be no different for Zeta II, allowing cosmetic external panels to be replaced. Holden and HSV also have plastic panel experience, with the thermo-moulded SMC sheets used in HSV Maloo tailgates. Like a woven mat heated into a mold, which once catalysed is strong enough to support the weight of a large man jumping on it. Testing included 10,000 slams, harder than a human arm could produce, to validate it.
Plastic Fantastic: HSV Maloo has a plastic, double-wall SMC plastic tailgate.
Holden believes in spreading technical improvements across the range: hence SIDI and six-speed transmissions became standard across the MY 2010 range once introduced; as did the Series II aero-improvement measures. There are no special 'Eco' models: the most efficient VE Series II models for economy and emissions are the 3.0 litre Omega and Berlina entry-level models.
2014 VF Commodore/WN Caprice (Zeta II)
- Omega - 3.0 LF1/6L50 trans (base business/fleet model)
- Berlina - 3.0 LF1/6L50 trans (entry family)
- SV6 - 3.6 LFX/6L50 or Aisin 6-speed manual
- SS - 6.2 Gen V DI LT1 with 6L80 or Tremec 60xx manual trans
- SS-V as above with higher level trim/luxury features
- Calais - 3.6 LFX/6L50 (Luxury model)
- Calais V - 6.2 Gen V DI LT1/6L80
- Clubsport R8 - 6.2 Gen V8 SWB sedan
- GTS - 6.2 Gen V 6.2 V8 SWB sedan (Magnaride)
- Maloo (Ute) - 6.2 Gen V 6.2 V8 LWB coupe utility
- Grange (Caprice) 6.2 Gen V V8 LWB sedan (Magnaride)
Long Wheelbase Models
- Caprice - 3.6 LFX/6L50 V6 (entry LWB sedan)
- Caprice V - 6.2 Gen V DI LT1 V8/6L80
- Ute - Omega, SV6, SS models as above
- Chevrolet Caprice PPV 6.2 LT1, 3.6 LFX (North America)
- Chevrolet 'SS' 6.2 Gen V DI V8"
- Chevrolet Lumina LFX 3.6 V6 (Middle East/South Africa)
- Chevrolet Lumina SS 6.2 LT1 "
- Chevrolet Lumina Caprice LFX 3.6 V6 "
- Chevrolet Lumina Caprice SS 6.2 LT1 "
- Buick Park Avenue 3.0 LF0 (Local assembly China)
- Daewoo/Chevrolet 3.0 LF0 Veritas (Korea)
- Chevrolet Special Vehicles SS M-E 6.2 Gen V DI V8
- Vauxhall VXR 6.2 Gen V DI V8 (HSV Clubsport, Maloo, GTS)
- Chevrolet Omega LFX 3.6 V6 (South America)
GM Inside News formulated a set of questions for GM Holden regarding existing and future Zeta. Obviously, as VF release is still subject to Commercial-in-Confidence, there are limits to the answers Holden could give. However, Holden's Social Media & Digital Communications Manager Andrea Mathews (poster HOLDEN on GMI), in concert with Emily Perry, Holden External Communications Manager, got their heads around our questions and answered as fully as they could, without disclosing sensitive information.
We can't answer many of your specifics as we don't comment on forward products or strategy.
I've answered where I can but know you will understand our need to protect our competitive advantage by not giving away too much.
-We know Zeta II is going to layer-build: what additional flexibility could this potentially bring as part of the core used for sedans - for instance as a large commercial vehicle or SUV.
Sorry - can't answer this
-We understand Zeta II will be more than fascia changes; will the greenhouse/door openings and pillars change as a result?
Again, we're not commenting on future models or design features
-Can we get an indication Holden thinking about the influence of overseas markets - has it changed since 2006?
The world has become a different place since 2006. We've rebuilt our manufacturing business to be sustainable and profitable on our domestic business alone. Holden employees would love to see our cars back on the roads in markets like the US but presently, overseas volume is being viewed as additional to core business.
-What is the consensus within Holden on the G8 program? Specifically, was it tracking to being profitable before the cancellation of the program and closure of Pontiac?
I can't give you a "business/financial" response as we don't comment on the profitability of individual programs. I can say that from my own perspective as a member of the enormous team that brought G8 to the US, Holden was immensely proud of the G8 export program and seeing Australian built cars on US roads.
-With GM's well publicised financial difficulties around 2006, how close did we come to NOT getting a Ute or Sportwagon?
Do you mean Australia? If you mean the US, then the Ute was a confirmed program for Pontiac and it was going ahead as per our internal timings, until it was cancelled. Sportwagon was never a confirmed export program for the US.
-Is there a corporate line on why Caprice is not going to be available for US retail market when it appears it could fit into two brands?
This is a question for Chevrolet - we don't comment on markets in other countries.
-Could Zeta 2 underpin any future products produced abroad, like in China and NA? We have heard of a RWD project called Omega supposedly being developed in China. Is this an adjunct or offshoot of Zeta or something else?
Holden cannot comment on global development.
-Are any Holden Zeta specialists working with GM North America on the Alpha project?
We don't comment on who is working on individual projects. Zeta is a global engineering team so GM moves people around the engineering function dependent on their skills/expertise and development requirements.
-How significant a role will exports play in the future of VE/Zeta products at Holden - or is this somewhat secondary to the primary role as an Australian-market vehicle?
See comments above.
-Are further upgrades in line for the current model prior to release of VF?
We have already announced a dedicated LPG model Commodore is on its way and we will be expanding E85 compatibility to 3.6l engines (currently only available on 3.0 SIDI and V8s)
Social Media & Digital Communications Manager