Admittedly, I was skeptical about the missing cylinder. Memories of 3 cylinder diesels aren't pleasant, what with the unrefined Polo 1.2L or the crude & shaky 1.5L CRDi in the Accent. My top 2 concerns were excessive vibration & turbo-lag.
Chevrolet has badged its diesel as the
Smartech TCDI. This 936cc DOHC 12v engine is rated at 58 BHP (@ 4,000 rpm) and 150 Nm of torque (@ 1,750 rpm):
The air-intake now moves to the right:
Quick look at the vital stats relative to other diesel hatchbacks. Least power to weight of all competitors, yet the torque to weight is on par with the Figo. The Marutis are about 20% ahead in the power to weight standings:
Crank the engine and the first thing you notice is the lack of any rocking motion felt on the steering wheel & gear lever. The vibrations are superbly controlled! This is much unlike the Polo, where you can feel a certain amount of vibration at idle. The motor is loud on the outside though, but that's only till you shut the door & windows. The Beat's heavy insulation keeps NVH at satisfactory levels on the inside upto 3,000 rpms.
Driveability within the city is a strength of the Beat TCDI. Typical of mild turbo applications (like in the Micra & Figo), there is a minimal amount of lag from the fixed geometry turbo-charger. Useable torque is available right from 1,600 rpms, a factor that greatly aids driveability. You can literally use 2nd or 3rd gear (depending on traffic density) as an automatic in typical urban driving conditions. The short gearing is ideal for puttering about in the city, and always keeps the engine in
turbo zone. For instance, in 2nd gear at 30 kph or 3rd gear at 45 kph, the engine is already spinning at 2,000 rpm. Throttle response is very good under such driving conditions. Turbo-lag is hardly a bother, unlike the Marutis that suffer from it uptil 2,000 rpm. Fact is, you will need a down-shift to 1st only when coming to a dead halt. The rest of the time, you'll find the 2nd & 3rd gear ratios to be amazingly tractable. You can even cross speed breakers in 2nd gear itself, as long as you wait for the exact one second that it takes for the rpm to climb, & the turbo to start spooling. Mid-range is satisfactory as well, with the engine delivering useful torque through the 1,600 - 3,600 rpm band. The diesel Beat is far better in the city than its petrol sibling, thanks to nearly 50% more peak torque that is made at a far lower rpm. It's no scorcher though, and outright performance upto 100 kph can best be termed as "adequate". There is none of that
sudden punch that the Swift diesel gives you at 2,000 rpm, with the Beat's power delivery remaining fairly linear. It's not peaky in nature at all.
While the lack of significant lag & short gearing give the diesel Beat superb in-city driveability, it's a different story on the highway where you will find that patience, indeed, is a virtue. This car is for the sedate driver, and not for the ones in a hurry. The Beat diesel doesn't have a problem cruising in a straight line at 100, or even 120 kph. But highway overtaking manouveurs need to be planned & the motor runs out of breath on the open road easily. This is no Swift or Micra diesel on the highway. You cannot downshift at high speed, and expect instant torque delivery. The power-to-weight ratio of 56.50 BHP / Ton is immediately evident. At 120 kph, the small 3 cylinder motor is already working very hard to maintain momentum. Plus, there is no real progress after 3,500 rpms either. Sure, if you push it, the motor will revv to its 5,000 rpm redline. But it will do so grudgingly, and without delivering any real pep in the 3,600 - 5,000 rpm range. Hence, it's best to adopt a relaxed driving style on the expressway. The key to extracting optimal performance of this motor is being realistic, and upshifting at 3,600 even when in a rush. 3 cylinder engines are generally very fuel efficient and thus, the Beat's ARAI rating of 24 kpl. That for the Figo 1.4L, Swift 1.3L and Micra 1.5L are 20, 21.7 & 23.08 kpl respectively. The Indica eV2, however, maintains bragging rights with its 25 kpl rating!
Chevrolet has done a phenomenal job with controlling the vibrations of the 3 cylinder diesel. As mentioned earlier, the NVH is satisfactory at idle. Even while driving about in the city, the vibrations remain well-controlled and neither the driver nor passenger will be complaining of any harshness. Get moving and right upto 3,000 rpms, noise levels remain at acceptable levels. All that heavy damping & hydraulic engine mounts must be doing their intended work. On the other hand, the engine note is rather grumpy, especially over 3,000 rpm. There is the characteristic 3-cylinder engine thrum as the revv needle climbs too.
You will remember how I termed the gearbox of the petrol Beat as "rubbery" in my review. The Beat Diesel's shift quality felt better, and the throw is noticeably more positive. Conversely, the hydraulic clutch is a little more weighted than the super-light one of the petrol car. The diesel's clutch pedal has a longer travel too, while all of the action is in the final 20%; there is no bite until the top quarter of the clutch. The taller amongst us will find it awkward as our left leg is in a rather awkward position when getting off the pedal (at its topmost position).
Ride quality remains a strong point, with the Beat feeling compliant even over rough road patches. There is absolutely no bounciness or bumpiness that cars like the i10 & Santro suffer from. Chevrolet has clearly tuned the suspension for comfort. The Beat is nippy within the city, yet the handling is at best sedate at speed. I'm glad that the tyre width has increased by 10 mm over the petrol. Straight line stability is fine and safe enough. Sudden lane change manouveurs now don't result in the tyres squealing easily, as we saw in the petrol. Body roll, though, is noticeable in fast corners. This car is not a handler (a la Swift or Figo) nor will it please the enthusiast in you. Drive it as a city hatch, know her limits and you should be safe. Remember, this is meant to be a family hatchback. The steering is a new electric unit (petrol Beat uses a hydraulic steering) that will soon make its way to the petrol Beat as well. It firms up sufficiently at speed, and feels a tad more direct. In the city, the steering remains super-light and effortless to use, including at parking speeds.
Here's a video of the new TCDI engine: