At the heart of Proton’s largest SUV, the C-segment X70, is a new-for-2022 engine that’s lifted right out of the smaller X50. With identical outputs, can the smaller 3-cylinder 1.5-litre turbo-petrol lug along a larger, heavier machine just as capably?
Since the introduction of the X50 in late 2020, the question of which other Proton models its compact but punchy motor could find its way into was being asked. Now, we have a definite answer with it being transplanted into a vehicle a full segment up the ladder.
Alongside some visual tweaks, this year’s revision of the X70 was really about its powertrain. On paper, it’s hard to see this as an upgrade in the traditional sense with less power, torque, and a perceived reduction in mechanical refinement from its odd-numbered cylinder count.
However, it is a win in other areas. Its smaller capacity, that missing cylinder, and a number of design improvements over the ageing 1.8-litre unit mean improved efficiency as Proton claims fuel consumption reduced by as much as 7% in daily driving.
The bigger advantage here isn’t one felt by the customer, at least not immediately. Proton stands to shave a big chunk of change by offering both the X50 (Flagship) and now X70 with the same engine, meaning its powertrain supply chain, production and after-sales support will have a vastly reduced scope thanks to this streamlining exercise.
Keep in mind, though, that the 1.8T mill hasn’t been removed from the range entirely. You can still get it in the range-topping variant, which is about RM4,000 more than the 1.5T in Premium trim.
Last week, we got the opportunity to sample both on an organised drive event that took us on a variety of roads between Kuala Lumpur and Desaru, Johor. With decent time behind the wheel, we’ve now got a more fully formed opinion about how the engine feels in its new skin.
There’s no getting around the fact that outputs are identical to the X50 with 177PS arriving at 5,500rpm and 255Nm between 1,500 and 4,000rpm. Essentially, Proton is asking it to pull a larger, heavier load without any real tangible alterations.
Can it? Sure, why not….
Will it match it for performance? Of course not.
According to Proton, X50 Flagship’s published kerb weight is 1,370kg compared to the 1,615kg of the X70 1.5 TGDI Premium 2WD we were supplied with. Some 245kg of extra mass isn’t a trivial amount.
Compared to the larger 1.8T with its 184PS and 300Nm, the 1.5-litre 3-pot is down 7PS but it’s that 45Nm gulf in torque that’ll be the most sorely missed. Proton has clarified that it has a given unique calibration to the engine and 7-speed dual-clutch transmission to cope with these deficits, but that can only go so far.
The good news is that the X70, for the most part, drives identically to the ones we’ve sampled before. We’ve always known the JLH-3G15TD to be a strong performer, and that hasn’t changed. From a standstill especially, it pulls strong even with multiple adult passengers and some light cargo in the boot.
In typical driving, you’ll rarely ever feel the engine strain to keep up with traffic, but it won’t be pinning you into the backrest either - this is pretty much true of the 1.8T as well. It’s no slouch at high speed either, managing to easily sail past the highway speed limit provided you have a clear stretch to build up speed.
Its on-demand roll-on acceleration, though, is where the 1.5T falls a little short. If given a window to perform an overtake at highway speeds, the X70 now feels considerably more hesitant and ponderous. That confidence an X50 might have at seizing that passing manoeuvre is absent in the X70.
The reason might seem obvious: less power/torque, more weight. However, I reckon the gearbox is more at fault, lacking the immediacy needed to deliver the cog swaps that’ll extract the most grunt from the engine. Standing on the accelerator pedal to pass a slow-moving lane hogger won’t unleash the fury you’d expect. In fact, it’s pretty anticlimactic, even if you happen to already be in Sport mode.
A solution to this is to take matters into your own hand: the left one. Only by engaging manual override, keeping revs high, and tipping the shifter back (downshift) or forth (upshift) can you remove the mask of lethargy that the overly conservative gearbox mapping has put on.
It turns out that its 255Nm can pull the X70 quite cleanly, but you’ll definitely be hitting that higher end of its 2,500 rpm peak torque ‘sweet spot’ to maintain a good pace, and fuel consumption will spike as a result.
Overall performance, therefore, is definitely comparable, but in certain driving situations takes a noticeable amount more effort to extract from the 1.5 than the 1.8.
Here’s where the X70 truly does excel. That additional quiver and characteristic rattling engine note commonly associated with a 3-cylinder engine are almost completely absent here unless you put your ear right up to the front grille at startup.
The amount of vibration dampening measures and sound-deadening material Proton must’ve stuffed in feels….significant. Its engine cover feels as soft and absorbent as a yoga mat, so we can only imagine what else is wedged between the motor and the passenger cell to cancel out any ungainly shudder.
For all intents and purposes, there’s no perceivable indication that anything has changed under the bonnet over the X70s sold prior to June 2022. But rather than being characterful in less than flattering ways, Proton’s pursuit means the engine now seems very muted overall.
Whether it's low-speed acceleration or climbing to redline, the sensation as occupants that anything is happening up front doesn’t really exist. Luckily, that’s what the majority of buyers would much rather have than the alternative.
If I were to nitpick, it would be about the wind noise where the wing mirrors would whine at about 140km/h, or slower if encountering a strong headwind. Think of it as an audible reminder that you might want to slow down a little.
Should you be familiar with the X70 at launch, you probably wouldn't be able to tell you were driving something with a smaller engine that's lacking a cylinder. The differences might remain elusive until you push the unit hard but otherwise at a high-speed cruise or from a standstill, the 1.5-litre mill delivers and on our 2-day drive did not disappoint.
That said, this is still essentially the same X70 that Malaysians already fell in love with. It has the same shortcomings (some newer, such as the at-times unalert gearbox) and continues to excel in areas it always had. What surprises us most is how the engine managed to recede into the background, allowing us to experience the car while meeting, though rarely exceeding, our performance needs.
There's just something about cars. It's a conveyance, it's a liability, it's a tool; but it can also be a source of joy, pride, inspiration and passion. It's much like clothes versus fashion. And like the latter, the pursuit of perfection never ends.