In keeping with its renewed focus on performance, Dodge revealed a few additions and upgrades for the 2015 Viper SRT this week. The new Viper lineup gets more engine power, a mid-priced GT model and a few other tweaks.

The biggest change for the 2015 Viper SRT is the addition of the new Viper GT model, which slides in between the entry-level Viper and the Viper GTS. A few premium features put it a step above the base car, including a driver-selectable suspension system boasting Bilstein DampTronic Select shock absorbers with street and track settings, a five-mode electronic stability control, and a unique interior with standard Alcantara and Nappa leather seats.

The 8.4-liter V10 beating heart of the Viper gets a nominal upgrade to 645 hp (from 640) courtesy of engine calibration and transmission refinement. Torque stays put at an even 600 lb-ft, while highway fuel economy makes a small one-mpg step up to 20 mpg (11.7 L/100km). The Viper may still be Dodge's sports flagship, but even after its output increase, it now lags well behind the all-new Challenger and Charger Hellcat models in terms of raw muscle. Its 206-mph (331.5-km/h) top speed is a bit better than the Hellcat's, though.

The upgraded V10 works in concert with a Tremec TR6060 six-speed manual transmission that gets a revised sixth gear in GT and GTS trim, reducing engine noise on the highway.

The track-focused Viper SRT Time Attack package has been renewed into what Dodge calls the "TA 2.0 Special Edition." The performance-honed package generates even more downforce than the original thanks to a new rear wing and front-end aerodynamic tweaks. Those changes up downforce to 400 lb (181 kg) at 150 mph (241 km/h), from the 278 lb (126 kg) the 2014 TA package developed at the same speed.

The package also includes SRT upgrades to the Brembo brakes, spring rates, dampers and sway bars, along with a carbon fiber structural X-brace in place of the standard Viper aluminum X-brace. The Viper SRT TA 2.0 touches ground with Pirelli P Zero Corsa-rolled ultralight Sidewinder II wheels. Dodge will offer 32 TA 2.0 cars in each of three exclusive colors: the new "Yorange" option, Competition Blue and Venom Black.

Other Viper line changes worth noting are the new 40-model Ceramic Blue Edition Package with unique exterior/interior look, the new Stryker Purple (GT and GTS) and Yorange body color options, and new interior color combinations, including the all-new "Demonic Red" colorway.

Inside, the 2015 Viper packs a Uconnect 8.4AN infotainment system with a suite of Uconnect Access features. The system has an 8.4-in touchscreen, traditional physical controls and voice recognition features. The integrated high-speed data connection offers push-button emergency communications, voice-to-text messaging and Yelp location searching. Harman Kardon audio comes standard throughout the Viper lineup and SiriusXM service is available as an option.

Dodge plans to release final pricing information at a later date.

For more information on the sporty engineering that resides underneath these 2015 changes, be sure to see our original piece on the current-generation Viper, briefly branded "SRT" at the time.

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