Chrysler 300 with a Demon 170 Swap: What Buyers and Enthusiasts Need to Know

The phrase "Demon 170 swapped Charger" — and by extension, a Chrysler 300 built around the same concept — describes one of the more extreme engine swap projects circulating in the Mopar performance community. Understanding what's actually involved, what it means for a car's value and legality, and what separates a clean build from a dangerous one matters whether you're shopping for one or just trying to understand what you're looking at.

What Is the Dodge Demon 170 Engine?

The Dodge Demon 170 was a limited-production 2023 model built around a supercharged 6.2-liter HEMI V8 producing a claimed 1,025 horsepower on E85 fuel. That engine — a heavily modified version of the Hellcat's supercharged 6.2L — represents the ceiling of what Stellantis produced in a street-legal platform.

When people refer to a "Demon 170 swap," they typically mean one of two things:

An actual Demon 170 engine (or a Demon 170-spec build) pulled from a Challenger and installed into another vehicle
A supercharged 6.2L HEMI built or modified to Demon 170-level specs using upgraded supercharger components, internals, and fuel systems — sometimes called a "Demon-spec" or "Demon clone" build

The Chrysler 300 and the Dodge Charger share the same LX/LD platform, which is why this swap attracts attention. The engine bay dimensions, transmission tunnel, and mounting geometry are closely related, making a powertrain transplant more feasible than it would be in a completely different chassis.

How a Demon 170 Swap Into a 300 or Charger Actually Works

A true 1,025-horsepower swap is not a bolt-in procedure. The supporting systems have to match the power output or the build fails — sometimes catastrophically.

Key components that typically need to be addressed in a build like this:

System	What Changes
Engine	Supercharged 6.2L HEMI, Demon 170-spec or built to match
Transmission	8HP90 automatic (Demon used a torque-converter auto) or upgraded alternative
Driveshaft	Upgraded for torque capacity
Differential	Dana 60 or equivalent; stock units won't hold the power
Fuel system	High-flow injectors, E85-capable pump and lines if targeting full output
Cooling	Upgraded radiator, intercooler, heat exchanger for the supercharger
Brakes	Factory Demon used Brembo 6-piston front calipers — critical at this power level
Electronics/PCM	Calibration or standalone ECU to manage boost, fueling, and timing

A Chrysler 300 shares much of its underpinning with the Charger but has different front-end structure, cooling packaging, and weight distribution. A professional swap that accounts for all of these variables can produce a usable car. A budget build that skips the supporting systems produces a vehicle that may not survive a full-throttle pull — or may be genuinely dangerous to drive.

What Makes These Builds So Variable in Quality 🔧

Because there's no factory kit for this swap, every build reflects the choices — and the budget — of whoever built it. That variability is enormous.

Higher-quality builds typically include:

Documented parts sourcing (genuine Demon 170 engine or a reputable built engine)
Professional fabrication for mounts, fuel lines, and cooling
Dyno tuning with documented results
Upgraded brakes, suspension, and tires matched to the power level
Proper wiring harness integration

Lower-quality or incomplete builds may involve:

Mismatched ECU calibration producing unreliable or damaging fueling
Inadequate cooling leading to detonation or premature failure
Weak driveline components that haven't been upgraded
No documentation of what was actually installed

When shopping a built car like this, build documentation matters more than claimed horsepower numbers.

Legal, Title, and Registration Considerations

A heavily modified vehicle with a swapped engine raises real questions at registration and inspection time. These rules vary significantly by state.

Some states require engine ID verification at registration — a swapped engine may trigger scrutiny
Emissions inspection requirements can affect whether a modified vehicle passes legally
Some states use OBD-II readiness monitors that a custom tune may interfere with
Insurance on a heavily modified vehicle can be difficult to obtain at standard rates — specialty agreed-value policies exist but terms vary by provider
A title with a salvage or rebuilt brand is common on donor vehicles used in swaps — this affects resale value and insurability regardless of the build quality

What Buyers of These Builds Should Verify

If you're considering purchasing a 300 or Charger described as a Demon 170 swap, the following questions are worth asking — though only a qualified mechanic familiar with high-output HEMI builds can actually assess what's there:

What is the engine's actual origin and build spec?
Is there a dyno sheet, and under what fuel and conditions was it tested?
What driveline upgrades were made, and by whom?
Has it passed emissions and safety inspection in the state where it's currently registered?
What does the title show — clean, rebuilt, or salvage?

The appeal of a Demon 170-powered Chrysler 300 is real: a large, relatively understated sedan with supercar-level acceleration is a legitimate performance concept with a long history in the Mopar world. But the gap between a properly executed build and a dangerous one isn't visible from the outside.