Dacia has dramatically boosted the power of its Spring city car as part of a bid to offer a "fully renewed and enhanced driving experience".

The Leapmotor T03 rival was launched in the UK last year with a choice of either a 45bhp front-mounted motor – the lowest output of any full-sized car currently on sale – or a more potent 65bhp unit, but both of those options are being replaced by much more potent alternatives.

From early next year, the Spring will be with a 69bhp motor on the front in entry-level Expression form, or with a beefier 99bhp unit in top-rung Extreme trim - matching the larger, petrol-powered Dacia Sandero TCe 100 for outright power.

Dacia says the change is aimed at ensuring the Spring "can travel with ease in less urban areas and fit naturally into motorway traffic for a more comfortable driving experience".

Previously, the lower-powered Spring was the slowest-accelerating full-sized car available in the UK, requiring 19.1 seconds to get from rest to 62mph. 

Dacia has not given full performance details of the new motors, but says they offer "up to 20%" more power and torque between 50 and 75mph. The Spring 70 is said to need 10.3secs for that sprint, while the more powerful Spring 100 takes just 6.9secs.

Along with the new motors, Dacia has also equipped the Spring with a new 24.3kWh battery, which uses lithium iron phosphate (LFP) chemistry – a first for any Renault Group model – which is said to reduce costs, last longer and improve thermal safety compared to conventional lithium ion batteries. 

Renault itself is planning to transition its electric cars to LFP batteries over the coming years, beginning with the Twingo, 4 and 5 hatchbacks.

The new battery gives an unchanged 140 miles of range on the WLTP cycle, which Dacia says is enough to "easily cover a full working week with a single charge" - but can now charge at up to 40kW in the range-topping Extreme car, up from 30kW as standard.

The powertrain tweaks come alongside a raft of changes aimed at making the Spring more efficient and better to drive - building on various upgrades it received last year.

Chief among these are an improved braking system with more powerful assistance, a standard-fitment anti-roll bar and retuned suspension for improved stability and subtle new aero-optimising bodywork elements that cut the drag coefficient from 0.743 to 0.665.

Prices for the Spring are expected to remain broadly unchanged, so expect to pay around £15,000 for the base car and £17,000 for the range-topper.