ELECTRIC SUPERCHARGER GIVES THIS BEAST A BOOST
Like most human beings, I am enticed by forbidden fruit. Show me something I can't have and I want it. Doubly so for cars. Put simply, covetousness is both my vocation and my avocation, and if you can make said object of jealousy Italian, well, then there's my weekly stipend covered.
There are exceptions, however. For instance, I wasn't expecting all that much from this week's bit of Italian exotica. It was a Maserati, but it was an SUV — a Levante to be specific. It is the company's largest — and heaviest — vehicle, powered by a four-cylinder engine, and it's a hybrid, no less.
Perhaps, I should have read the spec sheet first. First off, the in-line four-cylinder engine in question is the 2.0T liberated from Alfa Romeo's fine performing — but slow selling — Giulia. Maserati added a bigger turbocharger, so 280 horsepower becomes 326 hp. That sounds better. As do the 332 pound-feet of torque.
It's all about the technology. The bigger the turbo, any hot-rodder will tell you, the bigger the boost. But as that same hot-rodder will also tell you, a bigger turbo also condemns your little four-cylinder engine to poor transient response — turbo lag. All the top-end power in the world is of little use if your weighty SUV can't get off the line.
And that's where Maserati gets creative. It turned to electrification to backfill that “hole” in low-end torque, but how they did it is — as with most things Italian — a little different.
First, they added one of those Belt- Starter- Generator (BSG) systems, also known as a mild hybrid. Essentially, the traditional 12-volt alternator is swapped out for a more powerful 48-volt unit and its extra output is devoted to adding a little extra torque to the wheels. Typically, that torque is transmitted directly to the engine's crankshaft via what we would commonly call the fan belt. And that's where Maserati adds a twist.
Some of the power from that BSG hybridization drives what the company calls an e-booster — an electrically driven supercharger. And unlike a turbocharger, which has to build up steam to produce power, an electric supercharger is always on duty. Like electric motors, an e-supercharger's forte is low-end torque. Combining hybridization with supercharging — again, computer controlled and electrically driven — is the perfect antidote to any paucity in lowend torque.
How Maserati combines the two is a little counterintuitive. In the Levante's “Normal” mode, for instance, the e-booster works alone to shore up all that turbo lag. In Sport mode, however, both the e-booster and the BSG hybrid hardware add to the engine's power output. In typical hybrids, the opposite would be the case: the electric hybrid components called on first and the e-supercharger only when power demands are high.
Maserati contends that the e-booster's low energy demands are an efficient way to boost that low-end torque.
Whatever its machinations, the system works. And while the 336 hp that result from that larger turbocharger are welcome, it's the confidence the engine displays at low speeds that really impresses.
Small turbocharged engines are always promising the performance of six cylinders with the fuel economy of four. The Maserati, for one, delivers. In fact, behind the wheel it feels like a really good naturally aspirated V6, never really needing much more than a couple of thousand revs to deliver the speed — and acceleration — desired. Even throttling up Europe's highest mountain pass — the famed Stelvio I keep writing about — at an enthusiastic pace fails to tax the BSG and e-booster. Ditto cruising the Italian highway at 150 kilometres per hour. This is one of, if not the best 2.0-litre four I have tested.
It should even deliver decent fuel economy. I can't personally attest to any cost savings because my time in the GT Hybrid was mostly blitzing autostradas or strafing Alpine passes, which, by the way, the big Levante does surprisingly well. European testing indicates something in the order of 10.5 L/100 km overall. Good news, right?
The bad news is that, for reasons I can't fathom, Canadians can't get access to this delicious little engine. But that is countered by the fact Maserati Canada will bring the new hybrid four engine as the base powertrain for its new Grecale, Maserati's smaller SUV.
As for the rest of the Levante, despite being a relatively dated design, it's aging well, especially the cabin. Its decor, instrumentation, and leather clothing look more luxurious than ever. And Maserati's latest infotainment system, at least the Italian version, is truly innovative. In navigation mode, there's a small vertical information bar that includes all manner of information pertinent to your drive including next gas stations, current speed limits and, most useful of all, extremely accurate warnings of upcoming speed cameras. This last was a godsend. Gotta love Italian technology!