Fastest four-door saloon in the world (1990) - Lotus Omega

THE LOTUS OMEGA - FASTEST FOUR DOOR SALOON IN THE WORLD

At the end of traversing the back roads of the Riviera, through numerous vineyards, the return leg of the day's trek was via the Autoroutes. Large signs display boldly "120 Km/h", we figure that it must be the posted speed limits. But wait, as we join the traffic, sixteen-wheelers seem to be roaring by. Other cars seem to be flying by our Lotus Omega travelling at 120 Km/h with such disdain that one wonders if 120 Km/h is the minimum speed limit. But wait, up ahead we slowly catch up with a Renault Cinq(R5) probably cruising just under 120 Km h We signal left and move to overtake at about 120 Km h But in our rear mirror there are flashing headlights of a Peugeot 205 GTI, the driver obviously impatient like a bat out of hell, gesticulating with his hands. Well, the driver certainly didn't seem too friendly, let's see what the Lotus Omega can do. We drop out of the tall (71 Km/h per 1000 rpm) sixth gear that this gear box has, which the mother company, General Motors has pinched from the ZR-1 Corvette. Find 3rd clumsily as there are so many gates, and slam home the throttle. For a short while the engine feels flat then as the turbochargers kick in, we feel the seat of our pants slide backwards over the leather lined seats, only to be restrained by the backrest. The large speedometer reads 150 Km/h. .180 Km/h . .200 Km/h at a rate one would associate with a tachometer! Phenomenal performance!

The rude "pug" is now rapidly disappearing in our rear view mirror. See what he thinks of that. This certainly is no ordinary Opel Omega he was dealing with. He should have known when he saw the large rear aerofoil that_was designed not just to be noticed but to negate rear lift, in other words maintaining downforce over the rear axle. There is an easy 220 Km/h on the speedo, shall we explore the claim of a top speed approaching 290 Km/h? It's only another 70 Km/h to go. But no, we see a toll booth rapidly approaching up ahead. Brake hard to get the speed down. The anchors are fully up to the task especially when they have been hogged out to the maximum size that can be accommodated under the large 17 inch rims. Would you believe that this car has actually a set of four different rims? By virtue of the Ronal five-fin design being orientated in the direction of the rotation, this makes left and right different. Then the rears are wider than the fronts and probably carry a different offset, so front and rear rims cannot be swapped either. Under hard braking there is a little tugging at the steering wheel as the tyres encounter camber changes. We try not to deploy the ABS, but it is reassuring that it is there in case we need it.

We haven't a clue as to how to tackle the unmanned toll booth up ahead so we take our time on the approach. Everything is written in French so the signs are no help. We stop right in front of the barrier and stare at the large wire basket that has arrows pointing at it and something about French Francs. Just driving up at the next bay was the Peugeot's 205 GTI's driver, he looks at us and smiles wryly as he give us the thumbs up sign in acknowledgement. Its good to know that he understands the power of this brute that we are in but we are still at a loss about how to get through. We give the GTI's driver a puzzled look and point questioningly at the toll booth. He gestures to us to throw the coins into the basket and he does so himself, and waves as he drives off. There is a car behind us now, quickly we throw the coins into the basket and watch as the coins fall into the center where there is a hole that feeds the machine. Then lo and behold, the barrier lifts.

Embarrassed and anxious to get going we fumble for 1st gear. Its a good thing that despite the many gates, 1st is easily engaged as one would a normal car, no dog-legged shift to the lower left. The revs are a bit high as we take off and there is a chirp from the huge 265/40 ZR 17 Goodyear gumballs at the rear. Still we keep he foot to the floor to ensure quick progress. The tyres are constantly at their traction limit all the way in 1st gear as we hear slight chirping as we traverse rippled tarmac after the toll booth. Heads turn as the dark green Lotus Omega tears away, including some gendarmes standing next to their patrol car. They watch for a while before going back to what they have been doing, seemingly disinterested in this 377 bhp missile. Did they know that the Lotus Omega can dispatch with the 100 Km h mark in a scant 5.2 seconds and not too long after, their 120 Km h speed limit? If they had, we would have seen them getting into their patrol car. Fortunately for us the exhaust note was more noticeable inside the car than outside, markedly subdued by the twin turbochargers that magnify torque to a now 568 Nm at 4200 RPM.

Back on route we contemplate a top speed run but decide against such fool-hardiness. Let someone else verify the claim we say, it is an academic point, and anyhow Lotus must have at least attained that speed during their own testing because their name is at stake here.

Lotus, the brilliant but seemingly unprofitable British company founded by Cohn Chapman has had a couple of owners over the years, one of them being Toyota but is now firmly in the hands of General Motors. Putting the Lotus acquisition to good use, GM has managed to get some successful cross fertilization within its fold. Witness the Lotus Elan that has the Isuzu engine, the Corvette ZR-1, engine tweaked by Lotus and now the Lotus Omega. If performance is image then GM has several aces up its sleeve.

Complete Omega 3000 GSi bodies are shipped to the Lotus factory and then they are dismembered, then rebuilt to new specs. Life in the fast lane, no, make that very fast lane calls for something out of the ordinary. The raw brutal horsepower has to be harnessed and harnessed well so that the car will not become an un-guided missile at every green light. Chassis bracing is performed at strategic points and additional rose joints are used in the suspension. Sounds like preparation of a Group A Rally car really. Of course the piece de resistance is the turbocharged engine which proudly displays the name "Lotus" across the cam cover. One cannot miss the reworked suspension. It is very stiff and traversing anything other than smooth pavement is uncomfortable. Coupled with the ultra low profile tyres the Lotus Omega feels fairly nervous over poorly paved surfaces. Also the absolute control that the driver has through the steering is pretty direct except for the interference of the power assistance. That heftiness expected of a car with such gargantuan tyres is missing. In fact it is about as heavy as the standard Omega, whether that was a design consideration from the beginning is debatable but at any rate it is unalterable at the current time.

There is no denying that the steering is incisively sharp. The Goodyears make sure of that and cling on tenaciously but they do not really give a progressive response as the limit is approached. The tyres stick right up to the limit then when they breakaway, move out quite rapidly, not helped by the greater terminal speeds attained at this point. This is characteristic of all ultra low profile tyres, so a period of acclimatization is mandatory before one can exploit the full potential of the Lotus Omega. Given our short time frame with the car, it was abundantly clear just how well the Lotus Omega clings to the road but equally clear was the awareness of not-overstepping the limit.

Perhaps in the engineers eagerness to make this a real usable and appealing super-saloon, they may well have dialed-in just a little too much creature comfort, if that is at all possible. Understandably, most of the customers will not be trashing this gem on the track or otherwise, hence the luxury features. The Connoly leather seats do not provide sufficient lateral restraint for those with a slim oriental frame though it looks snug enough for the Europeans. The previously mentioned assisted steering feel also detracts from the rock solid connection like that of a Porsche as much as it adds to driving ease and comfort. There are no complaints about the engine and six speed gearbox but the clutch is moderately heavy so one's initiation phase would very likely include stalling the engine.

While at idle, the engine remains remote and quiet, there is little aural indication of the awesome potential that is hidden under the hood. Even as you drive away, the off-boost lethargy makes this Omega resemble its lesser stablemates which is a good point as it makes trickling through traffic rather controllable, but is not helped by the clutch that seems to get heavier every additional minute one spends in grid-locked traffic. The straight six comes from the Omega 3000 GSi and Opel helps out by having the block strengthened by extra ribbing. To get the phenomenal 377 bhp and yet have sufficient low end torque, the engine needed an increase in swept volume. This was accomplished traditionally by increasing the bore and stroke, resulting in a 3615 cc displacement. Lotus takes over from here on. The engine is completely disassembled then rebuilt with the necessary Lotus modifications of course.

By enlarging the cylinder head capacity the final compression ratio drops to 8.2:1. This is necessary to accommodate the barometric force-feeding that the two Garrett T25 turbochargers provide. The smaller turbine builds boost at a faster rate but has less ultimate boost and boost volume, hence the reason for having two of them. With the twin turbo set up there is a swifter response time as well as even higher boost level. An air to water intercooler takes sufficient thermal energy out of the compressed incoming charge so that detonation is kept at bay. The fuel-ignition management system takes care of the rest of the power production process but it is not from Bosch but from the AC Delco Rochester division because it had some rather important features that the Bosch system didn't have like a "smart" boost control manager and a mass densitometer in place of the restrictive flap that the Bosch system uses. If all that technology manages to pump out a seemingly anti-social 377 bhp, don't fret, the Lotus Omega breathes out through twin catalysts to ease the conscience of those concerned about the environment, as if the planned 1100 Lotus Omegas would make a significant difference.

The six-speed ZR-1 gearbox was chosen because it was designed to handle to more than 500 Nm torque(568 Nm in this case) and to provide a tall enough gear ratio for cruising at warp speeds. That could not be provided by a five speeder because if 5th was overdriven anywhere close to the 0.50 : 1 like in the ZR-1's gearbox, performance would be severely blunted and the Lotus Omega despite its 0.31 Cd, would not be able to attain top speed in that gear. The severely overdriven ratio was promoted to 6th and a top-speed-attaining ratio(0.75:1) was issued as 5th. To get all that power usefully to the tarmac, a limited slip differential had to be used. This came from the rear diff of the Holden Commodore. The suspension remains largely as is, MacPherson struts up front and the 3000GSi's multi link semi-trailing arm set-up in back.

Even with the considerably stiffer damping and springing, the massive accelerative forces manage to force a squat from the rear suspension as the traction limit is reached. Apply on the wild side of 3000 RPM and you'd reduce the Goodyear Eagles to slicks in no time. Somewhere between 2500 and 3000 RPM gives the smartest getaways. Take off is traction limited unlike the Porsche 911 Turbo, because the engine sits up front and cannot provide the downforce like the rear-engined 911. Still despite that and the heavier body, the Lotus Omega slingshots to 100 Km/h in just 5.2 seconds, 85% of that provided by 1st gear alone. The Goodyears are constantly kept at their traction limits as the massive torque is fed to the rear tyres. Only the 911 Turbo gives more thrust when the turbocharger kicks in. Once on the way however, the superior aerodynamics of the Lotus Omega tells. Where the 0.37 Cd 911 Turbo stops at 272 Km/h, the Lotus Omega closes in on the 300 Km/h club at 285 Km/h.

Entertaining though the Lotus Omega may be in a straight line, any car that wishes to covert the title, "Super-Saloon" must be able to tackle the twisty bits as well as a hot-hatchback driven by Juha Kankkunen. Grip the Lotus has aplenty but it is the assisted recirculating ball steering that gets in the way. It is not so much the accuracy or the sharpness which is indeed incisive but it is the feel that detracts from total connection with the tarmac, the interface being a little too detached from the action. Perhaps the speed sensitive power assistance needs to be reduced at lower speeds. It may help because recirculating ball systems are not necessarily all bad, just witness the one in the BMW 5 Series. The commanding, upright driving position is a plus point here as one can see and accurately place the car without resorting to guessing like in a 911 Turbo or any other low slung exoticar. Moreover, being the size of an ordinary Omega, and with its ground clearance mostly intact, this Lotus Omega can go just about anywhere its lesser twin can. Not only that, it can carry four adults in comfort, five at a pinch, swallow a golf bag, enough luggage for a long jaunt and cruise at 200 Km/h with just 2800 rpm on the tachometer to almost any place on the European continent(roads and speed limits willing). Which 285 Km/h supercar can do that pray tell?

Our thoughts clear as we hand back the keys to the Lotus Omega. From the slight tremor in the hand it is obvious that the adrenaline is still pumping. This is one car that has more than enough power to scare you silly. Driving it with great discretion is certainly the better part of valour. It can be immense fun as long as one avoids the pitfalls of over-enthusiasm. Is there any possibility of the Lotus Omega being available in Singapore? Quite likely. The local agents may consider homologating the Lotus Omega if there is sufficient demand. The price? A ballpark figure would be around $400,000 ARF. Remember there are only a total of 1100 Lotus Omegas 440 of which will appear as Lotus Carltons in the UK and the balance to be shared around the globe. You'd better place your order should you want this limited edition collector's item.


SPECIFICATIONS CAR: LOTUS OMEGA

ENGINE
CAPACITY : 3615cc, twin-turbo
CYLINDER LAYOUT : In-line six
VALVES : 24-valves
BORE X STROKE :
COMPRESSION RATIO : 8.2:1
MAXIMUM POWER : 377 bhp @ 5200 RPM
MAXIMUM TORQUE : 568 Nm @ 4200 RPM

TRANSMISSION
TYPE : 6-Speed ZF manual
DRIVEN WHEELS : Rear, LSD

PERFORMANCE
TOP SPEED : 285 km/h
0-100KM/H : 5.2 seconds

SUSPENSION
FRONT : MacPherson Struts
REAR : Multi-link

BRAKES
FRONT : 330mm AP Ventilated Discs 
REAR : Ventilated Discs

TYRES
TYPE : Goodyear Eagle F1
Size : F: 235/45 ZR 17 R: 265/40 ZR 17
Kerb weight : 1527 Kg

PRICE : $400,000 in 1991

Final Production numbers: 950 (320 Lotus Carltons, 630 Lotus Omegas)
 

 

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