What American made muscle cars are the fastest ever?

Defining the "fastest" American muscle car ever is tricky because different eras had different standards of measurement and technological advancements. There's no single definitive answer, as it depends on what you consider "muscle car" (some definitions exclude certain cars based on features or engine size), what year it was built (technology changed significantly over the years), and how you measure speed (quarter-mile time, top speed, 0-60 mph, etc.).

However, several contenders consistently appear in discussions about the fastest American muscle cars:

* Shelby Cobra 427: While some debate its inclusion as a strict "muscle car," its powerful engine and lightweight design gave it incredible acceleration and top speed for its time. It's often cited as one of the fastest ever.

* Dodge Challenger SRT Hellcat Redeye/Demon: Modern muscle cars boast significantly more horsepower than their predecessors. The Redeye and the Demon, with their supercharged V8s, are incredibly quick in terms of quarter-mile times and 0-60 mph sprints. The Demon was specifically built for drag racing, making it exceptionally fast over short distances.

* Chevrolet Camaro ZL1: Various generations of the ZL1, particularly the more recent iterations, have been incredibly fast, boasting impressive horsepower and advanced technology.

* Ford Mustang Shelby GT500: Similar to the Camaro ZL1, the Shelby GT500's have consistently been among the fastest American muscle cars, especially in their latest high-horsepower versions.

It's important to note:

* Technological advancements: Modern cars with sophisticated electronics, traction control, and other features can achieve faster times than older cars, even with similar horsepower.

* Modifications: Many cars have been heavily modified, making direct comparisons challenging. Stock versus modified comparisons are essential.

* Track conditions: Track conditions significantly affect performance.

To get a precise answer, you'd need to specify the criteria (quarter-mile time, top speed, 0-60 mph), whether you're talking stock or modified vehicles, and the era you are interested in. Then, you could consult detailed performance testing data from reputable sources.