These engines are as fantastic to look at as the cars that surround them.
The Lotus Carlton re-wrote the rules for fast saloons - we pitch it against its spiritual successor, the Vauxhall Monaro VXR8.
If the context is wrong, everything changes. Look at this Lotus Carlton. Back in 1990, the notion of a four-door saloon wearing such vast tires was outrageous. The rears have a 265mm section and a 40 per cent aspect ratio, for heaven’s sake, and are mounted on 17in wheels. Madness! And what about those arches that cover them?
Here was the meanest, baddest, most daring definition ever of a Euro musclecar saloon, a Vauxhall Carlton so topologically distorted that it looked like those cartoons of giant-wheeled tuners’ nightmares you see on offer at racetrack accessories stalls. Scoops and vents and valances spattered the surfaces, menace oozed through every oversize panel gap. And this had the approval, the encouragement even, of General Motors, the company that couldn’t make its hot hatches handle for fear of litigation-triggering lift-off oversteer? Unbelievable.
But what is this big blue thing lurking nearby? It, too, is a big saloon with four doors and a Vauxhall badge, and it, too, has giant wheels under bulging arches. The difference is that the wheels are even bigger, the arches are not add-ons and the time is the present. That’s the context. And in it, for the first time, the Lotus Carlton actually looks demure.
Those Lotus wheels are no bigger in diameter than those fitted to the little Peugeot 207 warm hatchback currently sitting in my drive. The whole car is unfashionably narrow, even by the standards of its time. Long and narrow; that should be good for a benign powerslide.
The unlikeliest of projects
The Lotus Carlton and its Opel-based Lotus Omega sister, together known at Hethel as the Lotus 104, shocked the world on its 1991 launch. The tabloids called it the killer family car, because it could do 178mph and of course every dad in the land would load up the Carlton and demonstrate how this was the world’s fastest saloon car because we are weak in the face of temptation. How could Vauxhall, and indeed Opel, be so irresponsible when a BMW M5 is so relatively sensible?
It didn’t help that the Lotus arrived just as Oxford’s Blackbird Leys housing estate discovered ‘joy-riding’ and insurance premiums for fast cars were rocketing. But arrive it did, costing £48,000 and bearing the bullish promise of 1100 replicas to follow. (In the end there were 320 Vauxhalls and 630 Opels, a total of 950.)
It was based on the Carlton GSi 3000 24V, completed examples of which were sent from Germany to Lotus’s factory at Hethel where they were partially stripped and the unused bits returned to Russelsheim. The straight-six engine gained a new, stronger, longer-stroke block to give 3.6 liters instead of 3.0, new pistons reduced the compression ratio to accommodate the twin turbochargers, and a water pump for the turbos’ chargecooler circuit occupied the space where the distributor had been
Two more water pumps, electric this time, helped cool things down after the engine had been killed following a fast run, and in all the Lotus possessed five heat exchangers of one sort or another including an oil cooler for the differential. That was a standard GM item, but between it and the engine was a gearbox taken from the Corvette ZR-1, keeping that car’s 45mph/1000rpm sixth gear but dispensing with the light-load lock-out that forced US ZR-1 drivers to shift economically from first to fourth when ambling.
This cramped hood fulf of engine was home to 377bhp and 419lb ft of torque, all aimed towards passing 60mph in 5.2 seconds and 100 in just 13.6 on the way to that scandalous top speed. Getting all that torque tidily to the road with just two driven wheels was a challenge, met by commissioning Goodyear to make some bespoke NCT tires with five ribs instead of the seven a tire that wide would normally have had. They chopped half a second from the 0-60 time because of the greater stability of the tread blocks.
AP Racing brakes hauled the Carlton down from the unfamiliar territory of compressed time and space, and a combination of geometry changes and self-levelling dampers kept the rear suspension’s camber change under control. Then there was the matter of accommodating those wheels, which involved some major cutting away of rear wings and doors. Lotus initially added those bonnet vents, too, but later Opel did it at its factory.
Behind the wheel of the super-Carlton
I could not believe how ludicrously fast this car was when I drove it in 1991, paired with a straight-six BMW M5 for a magazine twin test. I actually felt guilty about driving it, a familar refrain in today’s carbon-conscious times but an alien emotion back then. It was the torque that did it, a monstrous surge of energy which seemed to render an overtaken artic no longer than a Mini. If there was time to think about the potential success of an overtaking manoeuvre, there was time to do it.
All that elastically-delivered torque could be concentrate the mind on a wet road, though, in those pre-ESP days. I remember one long bend joining a dual carriageway on which the Lotus teetered on the edge of oversteer the whole way, but thanks to its innately benign balance it didn’t feel especially hairy. Apparently it looked quite heroic from the outside; like most Lotuses, it flattered its driver.
Only when sixth gear was finally engaged did the acceleration abate to normal levels, the gearing too tall even for 419lb ft to beat into submission. It was this gearing that gave the Lotus its huge maximum speed. Lotus didn’t set out to make Type 104 ludicrously fast; the pace was simply the result of relaxed gearing and easy cruising ability.
Australian muscle, Holden style
Sixteen years later, we’re at the Lotus test track with Vauxhall Heritage’s own Lotus Carlton and the car that in some ways reinterpets the idea for the modern world. In its native Australia, this latter-day Carlton is called the Holden Commodore VE HSV Clubsport R8. For the UK it’s renamed Vauxhall VXR8 and given dampers and suspension bushes better suited to the more vigorous driving that is possible here. A visually bombastic saloon with a 417bhp, 6.0-liter version of a Chevy small-block seems a pointless car in an Australia with such low and rigorously-enforced speed limits, but people can still fantasize and this is a good car with which to do it.
The V8, with an aluminum block nowadays but still two pushrod-actuated valves per cylinder, is broadly as used in the current Chevrolet Corvette and is again mated to a long-legged Corvette gearbox. There are some other distantly-related genes, too, in that the Commodore’s structure is a development of the 1993 Vauxhall/Opel Omega’s, the car that replaced the Carlton and original Omega. And if the VXR8’s £35,105 purchase price seems high for a Vauxhall saloon, especially one with some low-grade trim and clunky switchgear, it remains the cheapest way of transporting four people massively quickly in a new car. The VXR8 is also significantly cheaper than the Lotus was, especially as the pound was worth rather more back in 1991.
On the drive from Vauxhall’s Luton office to Hethel, the VXR8 seems to antagonize the more sanctimonious of our fellow motorists. Maybe it’s that deep air intake below the front bumper, or the angular rear wing, or the blattering bark of that V8. It is fast, though: 60mph arrives in 4.9 seconds, and while no top speed is quoted it’s going to be pretty huge.
And it’s proving quicker than the Carlton, a car which – in contrast to its 1991 performance – apparently antagonizes no-one because even a humble Corsa looks like a concept car nowadays. Yes, the outright acceleration figures suggest that this should indeed be the case, but what has happened to the Lotus’s space-time-continuum compression? Have we become so used to really fast modern cars that the Carlton no longer feels so unfeasibly quick? Or is something not quite right?
It doesn’t steer quite as keenly or feel quite as crisp in the chassis as I remember, either. At Hethel we’re about to reintroduce Lotus chassis guru Roger Becker to the car he helped develop, with its new equivalent for comparison. Then we’ll know if my memory is playing tricks.
Making the comparisons
‘The steering is not as it should be,’ says Roger as I’m pressed against the deep side bolster of the Carlton’s leather seat and the tail takes once again takes a wider radius than the nose. ‘The effort is higher than I remember and the vagueness is bigger.’ We head through a twist and up the straight, then hurtle right. ‘It’s very benign compared with how it was when we started, but this feels softer than I recall and the roll gradient is more than I remember. The road messaging feel is not as crisp as it would be when we developed the car. And the engine had more of a bullish feel. This one hasn’t got that snap and bite.’
So my memory wasn’t playing tricks, because I can’t think of an engineer more objectively calibrated than Roger Becker. We come to a stop, upon which the water plumbing makes a gurgle just as I remember from that road test car. ‘It’s on the wrong tires. The ride and steering would be firmer on the proper NCTs.’
The problem is that the proper NCTs aren’t available any more, but there must be something current that’s closer to required Carlton characteristics. It’s a tricky business when cars have bespoke tires, because a few years down the line you can’t get them any more. And so to the VXR8, wider, heavier, millennially butch. ‘ I couldn’t live with this steering wheel,’ Roger says as he wrestles with the rim’s lumps and bumps, ‘and I’d have cushioned the throttle. It jerks the car.’
Into the Hethel hairpin again. ‘I’m surprised at the roll angle, but the steering precision is much better.’ (The VXR8, unlike the Lotus, has a rack rather than a box.) Down with the accelerator again. ‘This is a bit more pendular and will lash out sideways a bit quicker, and I don’t like the dive under braking. But it’s very controllable and I don’t feel it’s getting away from me.’ It seems the VXR8 lacks the subtlety Lotus would always engineer into a car, that it’s more bruiser than sophisticate.
The point, though, is that this Lotus is 16 years old yet compares well with its brand new relative. We thought the Carlton range quite futuristic on its launch, with its low waistline and flush-fitting side windows like an Audi’s. All right, the future didn’t turn out that way and parts of its cabin are very crude, but back then no-one had made a saloon faster than a Lotus Carlton. All this one now needs is some attention from those at Lotus with the knowledge.
The phones were ringing the very next day.
‘GM had just bought Lotus,’ says Tony Shute who honed the Carlton’s ride and handling and nowadays heads Lotus’s advanced projects, ‘and they wanted a performance flagship. It took a bit of political persuasion within GM, but [engineering chief] Bob Eaton took us under his wing. He was quite a brave driver.
‘To warrant a Lotus badge, it needed a proper Lotus powertrain. So we came up with a definition of engine output and how to contain it in a two-wheel drive car, while Goodyear developed the tires for us before such fast cars were on the market.
‘We had to do the Vmax runs at the Nardo bowl with worn tires, otherwise there would be too much heat and catasrophic failure. We used the same car for Nardo and Arctic Circle tests, and we got 186mph on the straight at the Nordschleife. It was an absolute hoot in the Arctic.
‘Getting the on-centre steering response was very hard. We added an extra link to the semi-trailing rear suspension arms [a mod carried over to the GSi 24V] and added self-levelling to keep the camber right. There was a lot of negative camber on full deflection and the tires were very camber-sensitive. Mika Hakkinen was driving for us at the time and he spun it, because the car was too slow in its responses for him! It’s a different dynamic for a Formula One driver.’
Andrew Arden worked on the engine’s development, including many nauseating runs to develop a lubrication system free of oil surge. ‘We did that testing on car V2, the only red one ever built. Some prototypes were silver-grey but all the production cars were dark green. There were 10 or 12 prototypes and V1 was real mule.
‘There were ever-increasing demands on what the performance sign-off should be. Simon Wood, the programme manager, wanted it to as good as the LT5 [the 32-valve, four-cam V8 Lotus developed for the Corvette ZR-1] if not better. Sometimes we had them running for two or three hundred hours at peak power. The intercooler put out enough heat for an average English house.’
The memories flood back as the two engineers recall days before computer-aided design, when everything was done on the drawing board. ‘It was a great project to be on,’ says Tony. ‘We were proud to put the Lotus badge on it.’