The 2014 Dodge Charger and Challenger are both striking designs, but Fiat Chrysler says big visual changes are in store for both models for 2015. The company will show off its overhauled 2015-model muscle cars in New York later this week. Photo credit: Fiat Chrysler

Fiat Chrysler (NASDAQOTH: FIATY) is set to unveil overhauled versions of its iconic Dodge Charger and Dodge Challenger muscle cars at this week's New York International Auto Show.

What should we expect?

Chrysler says that the Charger will get a "full-body makeover", while the Challenger -- which at least on the outside, hasn't changed much since its 2008 debut -- will be "new from the inside out". 

So will Chrysler's Italian partner Fiat mess with the icons of American muscle? Not likely, says Fool contributor John Rosevear. John will be in New York when Chrysler takes the wraps off of the new Challenger and Charger, and in this video he outlines what he expects to see when the covers come off on Thursday.

A transcript of the video is below.

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John Rosevear: Hey Fools, it's John Rosevear, senior auto analyst for Fool.com. The New York International Auto Show starts next week, media days are next Wednesday and Thursday, and we're expecting the automakers to unveil several interesting new models.

I'll be there with my Foolish colleague Rex Moore, we'll bring you a video report of the show's highlights at the end of each day, and we'll have a bunch of more in-depth reports for you over the next week or so after that.

One of the places we'll be checking in at is the Dodge stand. Chrysler said this week that they will be showing off updated versions of their famous muscle cars, the Dodge Charger sedan and the Dodge Challenger coupe.

The Challenger of course was introduced way back in 2008 and hasn't really had a lot of changes since, the exterior styling is unchanged, though the car itself has been refined and enhanced several times since then.

But Chrysler says the 2015 Challenger will be, and I quote, "new from the inside out", and it will feature "a new powertrain combination that is sure to get enthusiasts "abuzz."

We've heard some rumors about what might be in store for the Challenger, some folks who seem to know about these things are saying that just as the current Challenger draws its stylistic inspiration from the original 1970 Challenger, the 2015 model will draw inspiration from the 1971 model, which was similar to but different from the 1970 edition.

As for that new power train that will leave us "abuzz", we've been hearing for a while that Chrysler has been working on a supercharged version of its Hemi V8, it'll be 6.2 or 6.4 liters depending on which rumors you believe, and it's expected to be good for well over 600 horsepower which will put it right in the range of the Chevy Camaro ZL1 and the outgoing Shelby GT 500 version of the Ford (F 6.10%) Mustang.

Don't expect it to be cheap, the ZL1 is priced around $56,000, and this new Challenger should be priced in that neighborhood. This new supercharged Hemi has been referred to by the code name "Hellcat" throughout the Internet rumor mill, but the "abuzz" in Chrysler's press release suggests that this engine might get a name like "Hornet" or something when it debuts.

Chrysler also said the 2015 Charger would get an overhaul, which is interesting because it was last redone for the 2011 model year, which isn't that long ago. But Chrylser is saying that the 2015 Charger will get -- and this is a quote -- "a full-body makeover with nearly every single body panel being resculpted."

They also say that the result will be "a sleeker, more modern appearance". So not an all-new Charger, but definitely a significant refresh. The modern four-door Chargers going back to the 2006 model have kind of had this mean junkyard-dog aesthetic going for them, riffing off of the big grills we've seen on the Ram pickups and so forth, very brash and not subtle. It's going to be interesting to see what they do to make it "sleeker".

We'll be there in New York when the new Charger and Challenger are unveiled, and we'll have a full video report for you from the show floor next week. Thanks for watching.