Perodua’s long-awaited compact SUV, the Ativa, is the talk of the town. Based on the attractive Daihatsu Rocky/Toyota Raize and utilising more of its Japanese partner’s technology than ever before, the D55L promises to be the most advanced Perodua ever – marking a new era for the national carmaker.

UPDATE: We’ve driven the new Perodua Ativa! Read our first impressions review here.

So far, we’ve looked at the specs, name and pricing; here, we’re taking a deep dive into the Ativa’s new engine, the 1KR-VET. Utilising just three cylinders and 1.0 litres in displacement, it will mark Perodua’s first foray into the world of turbocharging, making it bang up to date with the industry trend of downsizing.

Same block as Bezza and Axia, simple turbocharger setup

As the name suggests, the 1KR-VET is part of Toyota’s KR engine family, which also includes the 1KR-VE naturally-aspirated mill found in the Bezza and Axia. The lineup shares the same aluminium block, cylinder count and 71 mm cylinder bore, but the unit in the Ativa will have a scant 0.1 mm shorter piston stroke than the rest at 83.9 mm. This knocks two cubic centimetres off the displacement, dropping it down to 996 cc.

The engine’s stroke has likely been shortened to reduce the compression ratio, which has fallen from 11.5:1 on the Bezza and Axia to 9.5:1. This facilitates the addition of the already-compressed air from the turbo, which would otherwise cause knocking.

As is typical for a simple turbo engine, the 1KR-VET features a single-scroll turbocharger and a front-mounted intercooler. It’s this intercooler placement, not an additional oil cooler, that was being tested on a Daihatsu Thor mule on local roads in late 2019. That car originally came with a top-mounted intercooler; the Rocky’s longer front end allowed engineers to reposition it for greater efficiency.

New head with twin intake ports and injectors, multi-spark ignition, combined exhaust port

To keep costs down, the 1KR-VET gets multi-point injection rather than the more expensive direct injection technology. To compensate, this engine variant gets dual intake ports (meaning there are six ports on the intake side), each with their own low-penetration injectors. This design increases the atomisation of the fuel, allowing for more complete combustion – which, in turn, improves both performance and fuel economy.

As part of the Daihatsu New Global Architecture (DNGA), the combustion process has been further improved with multi-spark ignition. No, the engine doesn’t come with twin spark plugs – instead, it fires each spark plug twice in quick succession. This adds power to the flame kernel initiated with the first spark and allows the flame to propagate more quickly, allowing the mill to run leaner at low revs.

On the exhaust side of the cylinder head, the exhaust ports are combined into a single opening, which increases the temperature of the exhaust gases. The catalytic converter, positioned just downstream in the exhaust manifold, needs to be heated up to work properly, so the consolidation of the ports helps reduce emissions upon startup. The engine retains the Bezza/Axia’s variable intake valve timing, double overhead cams, timing chain and four valves per cylinder (12 in total).

Click to enlarge

In a bid to save weight and cost, the KR engines do not have a balance shaft to smoothen out the inherently unbalanced three-cylinder layout, unlike the more sophisticated 1.5 litre unit in the Proton X50. Instead, like the HR10DET in the Nissan Almera, the engine relies on a counterweights on the crankshaft alone. The 1KR-VE in the Bezza and Axia wasn’t especially successful in tuning out the vibrations, and it remains to be seen if things are any better with the 1KR-VET.

Significant power and torque increase, good fuel economy

Naturally, with a turbo in place, the 1KR-VET is significantly more muscular than the 1KR-VE, with outputs of 98 PS at 6,000 rpm and 140 Nm of torque from 2,400 to 4,000 rpm. Against the Bezza and Axia, the Ativa will have an advantage of 30 PS and nearly 50 Nm, which is not to be sniffed at. Those figures are also not a world away from the Almera, which has a similar 1.0 litre turbo triple and CVT configuration.

To enhance the sensation of speed, the Rocky and Raize get a Power button on the steering wheel, which remaps the engine and gearbox for quicker throttle response; it’s unclear, however, if the Perodua version will come with the same function.

But the turbo isn’t just good for power – Perodua is claiming an impressive fuel consumption figure 18.9 km per litre for the Ativa. That’s even better than the Daihatsu and Toyota’s 18.6 km per litre with front-wheel drive, although that number was achieved on the stricter WLTP cycle.

The downsized engine and stepless transmission go some way towards improving efficiency, but the Rocky and Raize also benefit from a start-stop system. The Bezza and Myvi already come with this feature, but the one in the Daihatsu and Toyota has been improved slightly, switching the engine off when decelerating from 9 km/h (up from 7 km/h).

Looking at the technologies, output figures and efficiency numbers on offer, we’re pretty sure most of you can’t wait to try out the Ativa for yourselves (and we can’t, either!). But what do you think – is turbocharging the right path for Perodua, or would you have preferred it to stick with a more conventional naturally-aspirated engine? Sound off in the comments after the jump.

GALLERY: Daihatsu Rocky in Japan

GALLERY: Toyota Raize in Japan

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