In the heart of Lisbon, Portugal, narrow stone streets snake between old buildings with double-parked cars lining the sides, leaving little room to navigate. Luckily, I'm behind the wheel of a 2018 BMW i3s, its small footprint well-suited for cramped urban conditions.

The i3s is a new addition to the i3 family for 2018, serving as the sporty option in the lineup. This variant of BMW's electric city car brings more power, enhanced handling and a slightly more aggressive visual presence. Software and hardware alterations to the electric drivetrain bump horsepower from 170 in the base i3 to 181 for the i3s. Torque also jumps from 184 pound-feet to 199. With the extra muscle, the i3s reaches 60 mph in 6.8 seconds and tops out at 100 mph to better the i3's 7.2-second 0-to-60 mph time and 93 mph top speed.

Official driving range ratings aren't available yet, but BMW says a full charge of the 33 kilowatt-hour lithium ion battery provides approximately 97 miles of range. With BMW's own charging station, the i3 can go from an empty battery to a full one in about three hours. Using a standard 110 volt wall outlet takes closer to 15 hours.

BMW's i3s packs a bigger 181-horsepower punch.

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For an additional $3,850, a two-cylinder gas range extender with a 2.3-gallon fuel tank is available for both i3 and i3s models. With the gas engine, range increases to about 180 miles.

Through the city, finding spots to experience the punchier drivetrain is difficult, but this stop-and-go driving displays the linear tuning of the throttle pedal. Smoothly launching from standstills is easily done, while a couple of open shots in traffic see the i3s whirl up to speed in a brisk fashion. Lifting off the right pedal reveals aggressive regenerative brakes that will bring the car to a complete stop.

Jam-packed streets also aren't ideal to experience the suspension revisions on the i3s, with its modified springs, dampers and antiroll bars that yield a 0.4-inch lower ride height and 1.5-inch wider track over the i3. Wheels also upgrade from 19-inch to 20s with Bridgestone Ecopia EP500 tires. At slow speeds, the ride is firm, but impacts are dealt with well enough for pleasant cruising. Steering is direct, with some weight tuned into the wheel that feels nice for maneuvering demands.

More aggressive bumpers, wheel arches and 20-inch wheels set the i3s apart.

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The Melbourne red metallic i3s garners attention from pedestrians at stoplights and other motorists as it tiptoes by. More aggressive bumpers, black-painted kidney grille insets, wider wheel arches and rear spoiler in addition to the aforementioned 20-inch wheels and lower stance bring a bit more visual pop than the standard i3.

Accommodations inside are pleasant, with plenty of room in front, but the seats could benefit with more side support. In back, there's space to squeeze in two average-size adults on short trips. Ingress and egress to the rear area isn't too shabby, either, with the suicide doors and the i3's B-pillarless opening afforded by the strong carbon fiber-reinforced plastic body shell. With 15.1 cubic-feet of cargo room, growing to 36.9 cubic-feet with the rear seats down, the i3s retains errand-running utility.

BMW's latest iDrive 6 infotainment system sets up shop in the center of the i3s' dashboard, featuring a 10.25-inch screen with the optional navigation system. My test car's excellent-sounding 16-speaker Harman Kardon surround audio system is an $800 add-on, while Apple CarPlay capabilities can be had for an additional $300. Android Auto users remain left out in the cold by BMW, though the company is still studying the implementation of the Android operating system into iDrive.

BMW iDrive 6 is standard with available navigation and Apple CarPlay.

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Safety tech includes a backup camera, while parking sensors, active park assist, autonomous emergency braking and adaptive cruise control are available as options. The latter works well when the drive route leads out of the city and onto the expressway, automatically accelerating and slowing with the flow of traffic.

On the open road, the i3s confidently barrels along at 80 mph, exhibiting impressive composure for a small runabout. Some tire noise from the 20-inch rubber and wind noise penetrates the cabin, but conversations with my co-driver are still possible at a normal voice levels.

The last exercise of the day with the i3s is through an autocross course to finally get a taste of its dynamic behavior. Punching up Sport mode calls up more direct accelerator response and tighter steering feel. Off the line, the electric car is a rocket. In a right hand sweeper, the i3s' turn-in feels immediate, and it hangs on tight through the corner. Blowing through a tight slalom and a lane change exercise brings a slight grin to my face before slithering through an absurdly tight chicane and across the finish.

After a few more runs, my time with the 2018 i3s is over. At its core, it remains a small and nimble city commuter with respectable driving range, interior accommodations and cargo carrying abilities. The new sport model is indeed a bit more engaging to drive, but don't expect people to give up the keys to their M2s, M3s and M4s for one.

With the recent recall issues BMW is having with i3, the on-sale date for the i3s still hasn't been confirmed, but BMW is targeting January or February. The i3s will begin at $47,650, which represents a $3,200 premium over the base model. If you want your i3s with the range extender, that will start at $51,500.

Is it worth the extra $3,200 to upgrade to the i3s over the regular i3? Probably not if your typical driving consists mostly of crawling through congested city centers. But if you frequent nice roads or hit up an autocross once in a while, splurging for the i3s may not be a bad idea if you are in the market for a small electric vehicle.