For $1, you can add more muscle to Dodge's newest muscle car

If you want a car with 840 horsepower that can go from zero to 60 in 2.3 seconds, it'll cost you $84,995. Plus another dollar.

That's the starting price for the Dodge Challenger SRT Demon, which Fiat Chrysler says is the most powerful production car ever.

The Demon comes standard with a mere 808 horsepower. But for $1, you get a crate of parts that set it up for the drag strip. This includes a high-performance powertrain control computer with a high-octane fuel setting that adds 32 horsepower.

The Demon is a one-seater. But another dollar gets you a front passenger seat, and the rear seat costs another buck.

The Demon's price includes a $1,700 federal gas-guzzler tax but does not include shipping. The car will reach showrooms in the fall.