New emission norms have prompted Mahindra to add common-rail technology to the heart of its best-seller, the Scorpio. It’ll be cleaner and greener, but has M&M also managed to make it a bit meaner, the winner we all know it could be?

“Improvement in the engine is immediately apparent.”

‘Power delivery is more linear now, so the Scorp is very driveable.’

MAHINDRA SCORPIO CRDe
List price (ex-showroom, Mumbai)
Rs 6.82-8.0 lakh (est)
Top speed 152kph
0-60kph 6.08sec
0-100kph 16.53sec
Kpl 11.5 (overall)
For Image, performance, value
Against Cramped cabin, uncertain handling

June 2002. The Scorpio is launched, to tumultuous response and superb sales. It romped home with our Car of the Year award in 2003; that year, its superb value, technology, looks and rugged ability were enough to get it the trophy. It handled like a drunk cow at speed, but it had grunt, space for seven, a fantastic sticker and that grille. To its credit, Mahindra & Mahindra (M&M) hasn’t rested on its laurels, and has been updating the Scorpio every once in a while. In late 2003, it received its first face-lift: its grille and bumper were modified, the interior upgraded with armrests and marginally greater space, and the engine’s camshaft changed from a gear-driven unit to a quieter chain-driven one.

March 2005. The engine has come in for its first major overhaul, gaining a common rail direct-injection system, taking the car firmly forward. The prime catalyst for this change is the new Bharat III emissions rule, which called for the cleaner and more controllable combustion of a common rail engine, but M&M admits that common rail, popularised as CRDi by Hyundai, is a potent marketing weapon as well. People just love the idea of common rail: it represents good value, high technology, refinement and a wonderful combination of greater performance and better efficiency. If it is as good as it sounds, the Scorpio could be a world-beater, but is it?
So, what's new? The common rail system, obviously, replacing the old distributor-type fuel pump. The conversion, carried out in-house with MICO Bosch, was extensive, including not only the new injection system but also a host of other modifications to the engine to handle the system.
For legal reasons, M&M couldn't use the name CRDi, and so stuck a CRDe label on the car, the ‘e’ standing, rather unimaginatively, for ‘engine.’ The injection system itself is called the BOSCH Common Rail System or CRS Generation 2.2; injection pressure is 1600 bar, leading M&M to modify the piston bowl to accommodate the higher pressure. The engine block is the same 2609cc unit, but the crankcase and cylinder head have been modified to take the new equipment; both remain cast-iron though.
The exhaust manifold was replaced by one made of a new material called Silimoly, which can withstand the 700deg C temperatures generated by the revised engine. There's also a new foam-type air filter, which lasts for 40,000km, and also reduces the drop in pressure to 20millibar.
Other long-lasting components include the new, spin-type fuel filter; oil changes will also be at longer intervals, of 15,000km. The turbo is new as well, the K04 unit replaced by a Borg-Warner K03, which is ‘softer’ and spools up quicker, reducing turbo lag and the abruptness of turbo boost.
M&M states it wasn't aiming for a big step in power — no one had asked for it, and the Scorpio didn't need it. Power has risen by 6bhp to 115 (M&M claims 120 could have been achieved, but this was given up in favour of a stronger bottom-end), and torque by 2.3kgm to 28.3. The aim was increased smoothness and refinement, better response, and of course, better emissions control.
Start it up, and you see it delivers. The immediate impression is that it is considerably quieter, especially at idle, though there is some turbo whine around 2000rpm. It's smoother as well, thanks to the common rail system: CRDi makes for better control over the combustion process, so combustion is less ‘peaky’ and abrupt, reducing noise levels. It is more perky and responsive as well, especially at the bottom end, the reactions both quicker and meatier. Turbo lag has been appreciably reduced, and the power delivery is more linear now, the torque curve smoother, without the sudden burst of acceleration when the turbo kicked in on the old car.
The Scorpio, always a good city car, is now even easier, more driveable through traffic, making up gaps in quick time, and getting more swiftly away from the lights. The figures speak for themselves: the CRDe is both faster in the 0-100kph sprint, taking 16.53sec to the old Turbo's 19.63sec, and is better through the gears as well — 20-80kph in the third gear is completed in a quick 13.69 seconds while the older one finishes a 40-100kph dash in 17.8 seconds, in the same gear.
The gearbox hasn't been changed much, except for a taller third gear, the ratio increased to 1.38:1 for better fuel consumption; however, the gearlever's action has been improved, and though it's still not very precise, the metallic clicking of the old box has gone, and the throw is slightly shorter as well. The taller third makes life easier on the highway, where it feels perfect for overtaking, but it's perhaps a bit too tall for the city, making you drop down into second a bit too often, despite the higher torque.
Top-end performance is better as well, the Scorpio now going from 40kph to 100kph in 17.07sec when shifted into the fourth, as compared to the old car's 23.7 sec, There isn't the dramatic leap in performance you'd expect from a switch to common rail injection, but there's a commendable improvement in refinement and smoothness. The difference in the fuel efficiency pattern of both the old and new Scorpios is marginal. The CRDe consumed slightly less fuel (9.7kpl) than the older Scorpio (9.5kpl) in the city. It, however, returned 13.4kpl on the highway as compared to its older brother’s 13.8kpl.
The chassis hasn't been changed at all, but there are larger 16-inch wheels, on slightly lower-profile tyres, which make for marginally sharper handling. Overall though, stability is still an issue, especially given the speeds the Scorp is capable of. It still rolls excessively (and alarmingly at high speeds), pitches around at the rear, and wallows too much. The brakes have been improved with more bite and quicker response, but still lack a linear feel, tending to grab at the last moment. They feel over-servoed as well: stab the brakes and the rear wheels lock up immediately. This is quite a pain, and can get scary if you're forced to brake mid-corner: over-compensate on the brakes and you'll be punished with a scream from the rear, and an already jiggly rear end stepping happily out of line. The biggest thief of confidence, however, is the over-light steering, which lacks feel, and is telegraph-like in its response and accuracy.
The flip side is a soft ride, which is great for low-speed city driving, and the Scorpio simply glides over potholes and broken patches. The larger wheels make the ride ever so slightly stiffer at low speeds, aiming for better control on the highway, but it is still very pliant and remarkably quiet. This, coupled with the hushed engine, gives a nice, plush feel to the car out of all proportion to its price.
Externally, there's no change, except for badging, larger wheels. The current rims will be replaced by stylised steel wheels, designed to look like alloys. The car pictured is the limited-edition Sportz, a stripped-down variant without power windows or side cladding.
The overhaul isn't complete yet: M&M admits this job was done very quickly to meet the April 1 deadline, and the engine will still need some fine-tuning and fettling. The interior remains largely unchanged for now, but M&M’s working on some options, like leather upholstery and ‘Captain’s chairs’ in the middle row.
Overall, the change is very successful, and although the common rail advantage could have been stretched further, it does its job in getting the Scorpio up to Bharat-III norms, and making it more driveable and refined.
It does cost you about Rs 30,000 more than the current car, a substantial increase, but it's worth it, and remember, the Scorp's still high value, and a very desirable SUV. There's still one last step, Mr Mahindra: fix the handling, give the Scorpio the chassis its new engine deserves, and you'll have something well nigh unbeatable. Does anyone have the number for Lotus?

COMMON RAIL: UNCOMMONLY GOOD
What is common rail? Why is it taking over the world? Common rail direct-injection is so much in demand because it delivers both quick response and torque, and good refinement. It is a development of the direct-injection diesel, which was fairly clean, but pretty unresponsive and as noisy as a pair of skeletons doing the rumba on a tin roof, and was used only on trucks and commercial vehicles.
Common rail solved that. This was a very high-pressure fuel line leading to all cylinders in a bank, instead of separate fuel lines for each cylinder, allowing high injection pressures (the Scorpio CRDe uses 1600bar). A diesel pump constantly delivers fuel to the rail, which feeds the injectors. The high delivery pressure of the fuel counters the pressure waves caused by the rising piston, so the engine responds well to throttle inputs. The common rail also allowed designers to use 'pilot injection,' a small amount of fuel injected microseconds before actual injection, to ‘warm up’ the cylinder. This steady rise in temperature means less abrupt combustion and a softer combustion note.
The result is better response and torque. Why common rail matters here right now is because it allows combustion to be electronically controlled, so emissions can meet Bharat-III norms.