Sales of the 707-hp Dodge Challenger SRT Hellcat and its four-door Charger sibling are smoking hot. So hot, they've been capped for 2015.

With the introduction of the new Chevy Camaro and the celebration of the 50^th anniversary the Ford Mustang, FCA’s muscle cars – Dodge Challenger and Charger Hellcats and the Viper – are almost getting lost in the shuffle … except with buyers.

In fact, sales are so strong that FCA US, the old Chrysler Group, capped orders for the hot-selling 707-horsepower Hellcat models. Dodge and SRT received more than 4,500 orders for the new 2015 Dodge Challenger SRT Hellcat in just the first five days after orders opened in September.

Tim Kuniskis, president of the Dodge and SRT brands, said the Hellcats have been a major success. Their popularity put too much pressure on the order bank because buyers were putting in multiple orders in an effort to secure one of the popular cars so they shut it down.

“Yes, the order bank is closed until ‘16s are (are ready),” according to FCA US spokesman Rick Deneau. “However, we are still validating, scheduling and building and orders already in the system before that.”

So far, however, FCA hasn’t released any sales numbers on the $60,000-plus Hellcats. However, as one door closes another one opens: Dodge is now taking orders for the 2016 Dodge Viper ACR.

The Charger version of Hellcat is sold out for 2015.

(Hellcat gets 22 mpg rating on highway. For more, Click Here.)

Unveiled recently at the revamped Conner Avenue Assembly Plant in Detroit, the American Club Racer model of the iconic, hand-built American supercar will have a starting U.S. Manufacturer’s Suggested Retail Price (MSRP) of $117,895, excluding destination charge and gas guzzler tax.

“Bringing our street-legal Dodge Viper ACR back is going to arm our track enthusiasts with the ultimate weapon to dominate road courses across the country,” said Kuniskis. “This is without a doubt the best Viper ACR ever. The latest in aerodynamic, braking and tire technology will ensure its legendary performance reputation around the world.”

(Click Here for details about Dodge’s fastest-ever street-legal Viper.)

Kuniskis said it is a challenge to rebuild Viper sales, following the success of the Hellcat, because both vehicles appeal to a similar group of buyers.

Dodge is now taking orders for the new 2016 Dodge Viper ACR.

However, Viper sales have jumped 40% since the car was repositioned with a price cut last fall, Kuniskis told reporters during a tour of the FCA US’s Viper plant in Detroit.

(To see more about how the Hellcat is one of the most collectible cars, Click Here.)

In addition to the price reduction, a new website and viral advertising campaign have helped spark fresh interest in the Viper, said Kuniskis, adding a new configurator that allows visitors to build their own, personal Viper has attracted more than 4,000 visitors since it went live about a month ago.