Here is the bad news: Dodge probably won't be building a convertible version of its Dodge Challenger. Here is the good news: For an extra $16,000, you can have your existing Dodge Challenger turned into something that looks like this one from the magicians at Coach Builders Ltd. It's up to you if you want to add on the Vortech supercharger that provides the 6.1-liter Hemi V-8 a total of 560-hp.