Plug-in hybrid powertrain technology is flooding into the performance car market as all advanced technologies tend to: from the top down.

It has transformed the modern hypercar into something we wouldn’t have recognised 20 years ago, and has left a big impression on the sportscar scene in the shape of the BMW i8. And while the lukewarm Volkswagen Golf GTE has given it an outing among hot hatches, that’s nothing compared to Peugeot’s 373kW all-wheel drive mega-hatch which is capable of acceleration and responsiveness that’s unmatched in the segment.

The R Hybrid’s primary power comes from Peugeot Sport’s 199kW 1.6-litre turbo four, but it carries 200kg of ballast in the form of an 85kW/201Nm electric motor for each axle and a 3kW/h lithium ion battery. Unlike other performance hybrids, the 308’s front motor drives straight into the Torsen limited-slip front differential, bypassing Peugeot’s six-speed automated manual gearbox. Both motors employ single-speed reduction gearing.

Peugeot 308 R Hybrid rear

So what does 373kW feel like in a family five-door hatch? I can’t tell you, because the unfinished 308 R Hybrid prototype only develops that much urge in launch control mode, which was off the menu during our brief test drive.

In the other modes – ZEV electric-only running, Hybrid and Hybrid Sport – it delivers a peak of 300kW and just over 540Nm; outputs that the high voltage electrical system can sustain for about five laps, or more unconditionally during road driving. Demand over 300kW for more than a couple of typical straights and you’ll have a very hot, very depleted lithium ion battery to nurse.

Peugeot 308 R Hybrid badge

But as usual with electrified cars, it’s not the outright power or performance that takes your breath away, but the flexibility and immediacy. In a high gear at 80km/h, flatten the accelerator and you’re shunted forward on a wave of AC-synchronous torque. Peugeot claims 80-130km/h in just 3.1sec in sixth gear (an RS3 takes three times as long), which makes this one of the most muscular cars of its kind.

Yes, the 308 R Hybrid powertrain has limitations. As well as the car’s fleeting delivery of its full 373kW, there’s its transmission. PSA’s automated manual ’box is cheap and light – I suspect it’s a 308 GTi unit with electronic actuators replacing a clutch and gearlever – but it’s not good enough for PSA’s current HYbrid4 line-up and no better here.

Peugeot 308 R Hybrid dash

Whether the 308 R makes production and at what price are decisions still to be made. But having demonstrated its enormous and intriguing potential, it seems Peugeot has a duty to see the project through.

Peugeot 308 R Hybrid side

Finally, it should be developed as a performance car, with handling and ride to suit. The car’s hybrid powertrain is much better suited to the demands of fast road driving than flat-out track work, and if customers understand that, they’ll be much happier campers in the end.

3.5 OUT OF 5 STARS

SPECS Engine: 1598cc inline-4, DOHC, 16v (+ two electric motors) Power: 373kW @ 6000rpm Torque: 730Nm @ 1900-5500rpm Weight: 1550kg 0-100km/h: 4.0sec Price: $100,000 (est) Like: Mid-range thrust; unrivalled performance in this segment Dislike: A new gearbox is vital; will it even come to Oz?