DETROIT – Lexus unveils the next-generation IS sport sedan this morning at the 2013 North American International Auto Show in Detroit.

The ’14 IS, on sale in midyear, carries over the current model’s 2.5L and 3.5L V-6 engines, but adds all-wheel-drive for the IS 350 and boasts new exterior and interior design, as well as a longer wheelbase, new multimedia features and improved ride and handling.

“I adopted an entirely different approach to the development of the all-new IS,” chief engineer Junichi Furuyama says in a statement. “Specifically, it was to make an entertaining driving experience a major premise behind all aspects of performance.”

Lexus says more spot welding, plus new laser-screw welding and adhesive body-bonding techniques, increase overall body rigidity from the outgoing-generation IS, which debuted in the U.S. in summer 2005. The added welding and bonding also makes for a more stable and comfortable ride but doesn’t affect handling agility, the Toyota luxury brand says.

A revamped double-wishbone front suspension, with 20% more sway rigidity, also is new for ’14. The rear suspension remains multilink but now uses the GS sedan’s system.

The IS also borrows its steering gearbox from the GS, with each gearbox component changed for more smoothness and accuracy, as well as better input response and driver feedback, Lexus says.

Both the IS 250, with the 2.5L, and IS 350, with the 3.5L, come in rear-wheel-drive and AWD configurations, a change from the current model which offers AWD only on the 250.

A hybrid available in Europe and Japan, the IS 300h, will not be part of the brand’s U.S. lineup, Lexus says.

Like most new Lexus models, the IS now has selectable drive modes, including Eco, Normal and Sport, and the IS 350-only Sport S+.

The IS 350 uses the IS F-Sport grade’s 8-speed automatic transmission with Sport Direct Shift, which makes for quicker shifts and offers full torque-converter lockup.

In Sport mode, the IS gets Lexus’ new G force Artificial Intelligence control, which “automatically selects the optimal gear and downshift pattern in response to G force” and holds the selected gear during cornering.

The F-Sport grade continues in the new generation of the IS, with exclusively-tuned suspensions and electric power steering.

The F Sport has a unique version of Lexus’ signature spindle grille, and the car’s front-bumper bottom corners get aerodynamic detailing to improve brake cooling.

The IS F Sport’s 18-in. wheels have a Y-spoke appearance similar to the wheels on Lexus’ LFA supercar.

Also inspired by the LFA is the IS F Sport’s moving center ring on its meter cluster.

Wide-flare wheel arches are a key design element of all ’14 IS models, as are a strong horizontal beltline and low-slung appearance, Lexus says.

Inside, the IS boasts a reworked front driver’s seat for better lateral support and a bigger rear cabin, made possible by a nearly 3-in. (7.6-cm) extension of the car’s wheelbase. Legroom for rear passengers is up 3 ins. due to the longer wheelbase and thinner front seats.

Electrostatic switches, which change temperature settings via touch, are new to Lexus and in the ’14 IS.

Next generations of Lexus’ Display Audio or Remote Touch-controlled navigation are on all ’14 IS models.

Lexus says its decision to offer real-time traffic and weather to IS buyers without a subscription via HD Radio is an industry first.

The ’14 IS gets 10 standard airbags and several optional advanced safety systems, including lane-departure alert and blind-spot monitoring.

The IS-F V-8 performance model, as well as the IS convertible, carry over from ’13 for ’14, Lexus spokesman Bill Kwong says.

In its nearly 8-year run, the current-generation IS hit its stride in 2007, selling 54,933 units, WardsAuto data shows.

For 2012, IS volume was well below that of BMW’s segment-leading 3-Series, which usually registers about 100,000 sales annually, and other Japanese luxury sport sedans.

Lexus IS deliveries tallied 27,708 in 2012, about 30,000 below Infiniti’s G model, while the 3-Series sold 99,602 copies.

cschweinsberg@wardsauto.com