Sunday, April 29, 2012

The Epica - Nameplate to Nowhere




The third version of a Daewoo platform which debuted in 1997 will disappear from our roads, to be replaced by a new GM ‘world car’ - the Malibu. The apparently-unloved Holden/Chevy Epica which was, in GM’s own words, ‘a disappointment’ may have been a poor seller, but the background behind this car, and its technological development is another fascinating chapter in the history of the automobile.
It’s also another case of great potential denied, because of circumstance, history and bad timing. The real interest for many automotive experts however, was not the car, but the compact, transversely-mounted, in-line six cylinder engine!
But first, the car. Just under three years before the launch of the Daewoo Leganza in 1997, the Project Director Dr. Woo-Jong Lee was working with Giugiaro’s Ital Design on the styling of the new model. Just a few months later he was in the UK with Lotus to start work on suspension development; then off to Germany to combine with ZF for a new automatic transmission. From styling ‘freeze’ to the first production car took just 34 months!
Daewoo Leganza (V100)

Leganza, codenamed V100, was built on a brand new platform, and Ital Design took its styling cues from a still-born Giugiaro design concept for Jaguar, called the Kensington.

Ital Design Kensington concept

The car remained in production until 2000, when it was replaced by V200 (also managed by Dr. W-J Lee). Named variously, the Daewoo Evanda, Chevrolet Epica, Magnus and Suzuki Verona; this car was also designed by Giugiaro, and in my opinion was a very handsome refinement of V100.
Suzuki Verona (V200)

They should have stuck with the Italians for design, because the replacement (codenamed V250) was styled completely in-house at the old Daewoo Design Forum in Bupyong, and was a great disappointment after the Magnus. This is the car which came to Australia as the Holden Epica, to sit between the Opel-bred Astra and Holden Commodore.
Holden Epica (V250)
The main reason given by GM for its poor sales was the lack of a four cylinder petrol engine. The car came with either a 2.0 litre, or 2.5 litre in-line six petrol; or a 2.0 litre four cylinder diesel. The car was well-built, well-equipped and well-priced, but it failed to ignite the buyers’ interest. The styling definitely sucked, and maybe needed the cool touch of an Australian designer from Fisherman’s Bend, like Mike Simcoe.

Thus, it will now be replaced by a Korean-built version of the Chevrolet Malibu, built off the new GM Epsilon II platform, and powered by a (hopefully) highly-efficient four cylinder engine.
Chevrolet Malibu
So, if we’re on to engines, this then is definitely the really interesting part of the background to V200/V250. The transverse, in-line six cylinder engine is a dazzling piece of automotive design and engineering. It was innovative, efficient, cheap to build and economical to operate; and was full of intelligent and unique design features - now sadly lost to history.
Named the XS series, the key to its ability to be located transversely in the engine bay of a medium-sized car, was its thin wall construction and very compact dimensions.



Like all good stories this one begins a long way before even V100 was contemplated.
In the mid 1980s Dr. Ulrich Bez, engineer Jiri Seidl and Dr. Andreas Truckenbrodt were employed by BMW’s ‘skunk works’ company, BMW Technik GmbH in Munich. The original concept was Seidl’s brainchild and was initially conceived for BMW because of the company’s fondness for in-line six cylinder engines.


The innovative element came with the decision on the bore centres (for the machines which make the engine block), because using identical bore centres the engine could be made in modular fashion as either a three cylinder, four cylinder, five cylinder or six cylinder - on the same production line!
XS cutaway showing thin wall design and compact block dimensions
The other element was the thin-wall design, literally cramming the cylinders together, and then employing special cylinder liners, with a high-tech coating to combat the heat, which is normally absorbed by thicker water jackets. 
However, probably one of the most innovative, yet immensely practical attributes of the compact engine design meant that an existing ‘standard’ transmission (rather than one uniquely-designed for this application), could be employed. The ZF transmission was able to sit ‘on the end’ of the engine, rather than ‘underneath’ (or some other complicated installation) - and this dramatically reduced the potential cost of the overall design.
The limits of the engine, however, were that the total capacity could never exceed 2.5 litres in six cylinder format. By never being able to ‘stretch’ the capacity mean’t there was always an upper limit on the engine’s power output - a concept not attractive to BMW, which was always looking for truly high-performance engines.
Thus the engine concept went into ‘sleep mode’ until Ulrich Bez joined Daewoo Motor Company in 1994, following its separation from GM. Daewoo’s mercurial Chairman Kim Woo Chong wanted to embrace higher levels of technology for a new range of cars, to be created under Bez’s leadership. Bez suggested the Chairman invest in a technical centre in Munich, run by Dr. Truckenbrodt, who had come over from BMW.
Bez and Truckenbrodt convinced the semi-retired Seidl to come and work on the XS series engine family and the first prototype appeared in 1995, built by a small engineering company called Ficht GmbH. Later, a larger engineering company based in Graz, Austria, called AVL, developed more prototypes.
Moving from drawing board to working prototype is a big step to realizing all the ideas which the three men conceived in concept form, and which highlights the truly innovative nature of the design.
Details from the engineering presentation to the Daewoo Motor Board in January 1997 makes an interesting study.
The engine was built with an aluminium block, head and oil pan; plastic intake manifold, plastic cam cover and tubular exhaust system as opposed to a cast manifold. These measures dramatically reduced the weight of the engine, optimizing its specific power-to-weight ratio. The target weight of 135kg, was slightly exceeded (155kg) when the engine went into full production, but nonetheless it was light for its size.
Lightweight tubular exhaust manifold
At the time, a comparable BMW engine weighed 165kg. This low weight also meant excellent fuel consumption, with a 2.5L XS dramatically beating a BMW 1.8L engine.
Bez and Seidl were also looking for high durability, and to that end employed a one-belt, chain-driven, nodular cast-iron camshaft, a thin (three layer) metal head gasket, Ferrite coated pistons and extended oil change periods. The team reckoned on achieving 100,000km-plus with 95% reliability.
Future developments included a provision for valve and cylinder deactivation; variable valve timing and variable intake manifold. The team also focused on high manufacturing technologies including aluminium liners with a sprayed-on protective coating, low-noise, low-friction, asymmetric, Elastobal pistons and specially-designed and nitrided piston rings to maintain reliability, but also low friction.
After successful prototype trials in 1996, Daewoo’s Munich-based team accepted that Daewoo did not have the resources for development of mass-produced engine tooling and manufacture, so the project was turned over to Porsche Engineering GmbH in early 1997.
The XS engine was brought to production in 2000, with the launch of V200 (Magnus) and featured all the benefits envisaged by its designers - light weight, excellent economy, low noise and NVH, and strong performance.


To clarify, this was not a 'Daewoo' engine. This was the product of three very bright European automotive engineers with many years of sophisticated design experience behind them. As evidence of how innovative this project was is the coating planned for the cylinder liners.


For a number of reasons, the industry 'stand-by', Nickasil, was not originally considered. The team looked at a brand-new plasma spraying technology from a small company called Sulzermetco, which was developing the technique for Mercedes to use on its V6 and V8 engines - so the humble Daewoo-funded engine was destined to use cylinder-coating technology developed for Mercedes-Benz! However, in the end the new process was not ready in time for production, and Daewoo was forced to revert to using Nickasil.
Chevrolet Magnus (V200)
The far-sighted planning of Bez, Seidl and Truckenbrodt unfortunately was never able to  realize the full potential of the original design under GM’s management. The American corporation plans for big volume numbers, and extremely low cost and this was an environment in which the XS couldn’t survive. It may have been cheap to produce (once all variants came on line); but it was also too complex for GM (which traditionally is not interested in high tech, high cost components).
As first conceived, the XS series could be economically built in a very wide range of sizes and capacities, as this table from the Daewoo Technical Centre Powerpoint presentation shows:

No. of Cyls
Capacity
M (Matiz)
T (Lanos)
J (Nubira)
V (Leganza)
3
800cc
1 litre
O
O



4
1.3 litre
1.5 litre
1.6 litre

O
O
O
O
O

6
2.0 litre
2.5 litre


O
O
O
Remember this was made both economically feasible, and efficient in a manufacturing sense, by having one bore centre for the transfer lines which produced the block. All versions could be made on the same production line!

The target assumptions, and prototype testing revealed excellent results.


Inevitably, in the GM engineering hierarchy the XS was too different from GM’s mainstream engine designs, too complex, required too many unique technologies, and thus in a corporation which often shaves cents of a new model to save costs, it was just too out-of-left-field.
What the project does highlight however, is the sheer intellectual genius of its designers. Dr Ulrich Bez is now COO of Aston Martin, Dr. Andreas Truckenbrodt runs AFCC (jointly-owned by Mercedes-Benz and Ford Motor Company), developing electric fuel cell technology, and Jiri Seidl retired to Prague.
It’s also another casualty in the battle between the survival of innovation, and the crippling effect of mass market cost pressures.
DRIVING THE EPICA
We take off to the west from the Queensland Gold Coast in the Epica CDXi and up into the mountainous hinterland, then head south through the Great Dividing Range, crossing the NSW-QLD border near Springbrook, and down into Murwillumbah for lunch. Then back through the hills, via Tomewin and Currumbin Valley to Surfers Paradise.


This is a great test route, as the road climbs and falls, with both tight and gradual curves, differing tarmac surfaces, and provides close to 200km of opportunity to gauge performance, economy and ride and handling.
First, the engine pulls strongly and is very quiet (unusual for a GM engine). As other road tests have reported the 2.0 litre version of the XS is pretty breathless and needs to be driven to the 6500rpm redline to extract any sort of performance - but the 2.5 litre has much more mid-range torque, and is easily the best choice of the two.
The ZF automatic transmission has been replaced now by a 6-speed GM design, the 6AT40. The combination of the 2.5L SX and the GM 6-speed works very well. The calibration of the transmission has been well-matched to the engine, and it's a pleasure to drive.
The ride is comfortable and the handling is positive, although the steering lacks feel. The secondary ride, thanks to the 2700mm wheelbase, is very impressive and this has to be attributable to the tuning that Holden engineers carried out at Lang Lang.
The McPherson strut front, and multi-link rear suspensions are well-tuned for our roads, and with excellent cabin comfort and legroom for the occupants, the Epica surprised by showing up as a good touring car for four adults. There’s no banging and clunking from the suspension on indifferent surfaces, and long suspension travel easily soaks up deeper undulations.



If the Australian market was big enough to handle profitable volumes of a light six sedan, pitched below Commodore, I have no doubt the Epica (despite its bland Korean styling) would have been an able competitor. However, with the main competition being cars with sophisticated four cylinder engines, like Toyota’s excellent Camry, it’s not hard to see why GM craved a four cylinder engine for Epica to be properly competitive.
However, here’s a question? In the planned lineup, with the current success of the Holden Cruze, where exactly does a four cylinder Holden/Chevy Malibu (Epica’s replacement) fit in? Seems like GM Holden may now have more models than it needs in this segment!


Heading back to the Gold Coast after a counter lunch in Murwillumbah, I remain impressed with the XS engine. Looking under the hood, it’s certainly a tight fit, but the engine delivers on all its targets. I even managed a commendable 8 litres/100km fuel economy for the round trip.
Thinking back to the first time I drove an XS-engined Daewoo Espero prototype at GM’s Millbrook (UK) Proving Ground in 1997, it is certainly a chalk-and-cheese comparison. Coming back from ten laps of the Hill Route circuit, I complained about lack of mid-range torque.However, the prototype engine did pull strongly, and was very quiet at maximum revs, as I thrashed around the circuit chasing a very quick Uli Bez.
Millbrook Proving Ground Hill Route

The Epica will pass from view, and by the sound of it will be quickly forgotten, but I think it’s place in the automotive firmament should be secured by the innovative technology represented by its very interesting, transverse, inline six cylinder engine - born under the rule of an eccentric Korean car company chief and German genius engineers. That’s not to forget Jiri Seidl, whose idea it was in the first place!

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