The Dodge Challenger 6.2 Hellcat is a modern muscle car icon, delivering an exhilarating 707 horsepower straight from the factory. But for enthusiasts who crave more, pushing this beast past 800 horsepower with forced induction is a rewarding—but expensive—challenge. This expanded guide breaks down every major cost involved in building a reliable 800+ horsepower Hellcat, from the base vehicle to the final tune. You’ll learn what modifications matter most, where your money goes, and how to budget smartly for a high-performance build that won’t leave you stranded.

The Hellcat Platform: A Solid Foundation

Before you even think about parts, you need a car. A new Dodge Challenger 6.2 Hellcat starts around $60,000–$70,000. Used models can be found for $45,000–$55,000, but be cautious: a well-maintained example with lower miles is worth the extra investment. The Hellcat’s cast-iron block and forged crank are stout enough to handle 800 horsepower with proper supporting mods, but the stock pistons and rods become a weak point if you push beyond 850. That’s why many builders budget for internal engine work from the start. The base car is your single biggest expense, so buy wisely.

Forced Induction Options: Supercharger vs. Twin-Turbo

Supercharger Upgrades

Most Hellcat owners start with a supercharger upgrade. The stock 2.4L IHI blower can be swapped for a larger unit like the 3.0L or 4.0L Whipple, a 2.7L Kenne Bell, or a Magnusson Heartbeat. A complete supercharger kit (blower, snout, intercooler bricks, and necessary plumbing) runs $6,000 to $10,000. You can also opt for a pulley swap and porting on the stock blower to save money (around $2,000), but that usually limits you to about 750–800 wheel horsepower. For a reliable 800+ at the crank, a full swap is recommended. Some shops offer package deals that include injectors and a tune.

Twin-Turbo Kits

Twin-turbo setups are less common on Hellcats but can produce immense power with better thermal efficiency. Kits from companies like Hellion Power Systems or Forced Induction LLC range from $9,000 to $15,000. These require extensive fabrication for hot and cold sides, wastegates, blow-off valves, and oil lines. The labor cost is significantly higher (add $3,000–$5,000). Turbos also require more meticulous tuning to avoid detonation. If you’re chasing 1,000+ horsepower, turbos may be the better path. But for a streetable 800–850, a good supercharger kit is simpler and more cost-effective.

Supporting Mods: Fuel System and Engine Internals

Fuel System Upgrades

To support 800+ horsepower, the fuel system cannot be stock. You’ll need:

  • High-performance fuel injectors: 1,000cc or larger (the popular ID1050x or Injector Dynamics) — $800–$1,200
  • Fuel pump upgrade: In-tank DW400 or triple-pump set‑up for e85 — $500–$1,000
  • Fuel lines and regulator: If going return-style (recommended for E85) — $400–$700

E85 is the preferred fuel for high-boost builds because of its high octane and cooling properties. However, it requires a larger fuel system and is not available everywhere. If you plan to run pump gas only, you can reduce fuel system costs by about $500, but you’ll be forced to dial back boost and timing to avoid knock. According to the experts at HP Tuners, a solid tune on 93 octane plus meth injection can also work, but it adds complexity.

Engine Internals: Pistons, Rods, and Heads

The stock Hellcat pistons are hypereutectic and not ideal for sustained 800+ horsepower runs. Many builders upgrade to forged pistons (Diamond, CP, or Mahle) and forged connecting rods (Manley or Callies). A full short-block build with upgraded pistons, rods, bearings, rings, and ARP fasteners costs between $4,000 and $7,500 for parts, plus $2,000–$3,500 in machine work and assembly. The cylinder heads can be left stock for 800 horsepower, but a port job and upgraded valve springs (another $1,500–$2,500) will improve flow and rev‑ability. If you’re planning to eventually go to 1,000+ horsepower, do the heads now to save labor later.

Drivetrain Upgrades: Handling the Extra Power

Transmission

The ZF 8HP90 eight-speed automatic in the Hellcat is robust, but at 800+ horsepower with drag radials, clutch packs and the torque converter become borderline. A full transmission build (upgraded steels, clutches, billet input shaft, and a higher-stall converter) costs $3,000–$5,000. Some owners opt for a $1,200 torque converter swap and hope the rest holds—but that’s risky at 800+. If you have a manual (rare in Hellcats), you’ll need a stronger clutch (McLeod RXT or similar) and possibly an aftermarket shifter — $1,200–$2,000. Labor for transmission work is separate, around $800–$1,500.

Differential and Axles

The stock limited-slip differential and half‑shafts can fail under track abuse. A built differential with upgraded clutches, a stronger carrier, and 1400‑hp rated axles from DSS or The Driveshaft Shop costs $2,500–$4,500. This is a critical safety item; a broken axle at the track can cause severe damage.

Suspension and Brakes

To put the power down, you’ll need suspension work: lower control arms, toe links, and sway bars (BMR or Hotchkis) — $800–$1,500. Coilovers (KW, BC Racing) add another $1,500–$2,500. For brakes, the stock Brembo six-piston setup is adequate for street use, but if you track the car, upgrade to two-piece rotors and high-temp pads ($1,000–$2,000). Brake cooling ducts are also recommended.

Cooling and Heat Management

A 800+ horsepower Hellcat generates enormous heat. The stock intercooler bricks in the supercharger are undersized for sustained boost. A killer chiller or a larger air-to-water intercooler system (like Cruz Performance) costs $1,000–$2,000. A high-flow water pump and an upgraded radiator (Mishimoto, CSF) add another $600–$1,200. Ignore cooling at your peril — heat soak can knock timing and cost you 50–100 horsepower on a hot day. Many builders also install an oil cooler and differential cooler ($500–$1,000 each).

Labor and Tuning Costs

Labor is where the budget can balloon. A forced induction installation (supercharger upgrade, fuel system, and exhaust) runs $2,500–$4,000 at a reputable performance shop. If you add short-block work and heads, the labor jumps to $4,000–$6,000. The tune itself is critical: a high-quality remote tune (like from Curt at Curtis Tuning or a local dyno specialist) costs $500–$1,200 plus dyno time at $100–$200 per hour (typically 4–6 hours). Do not cheap out on tuning — a bad tune can destroy an engine in seconds. Expect total labor and tuning to be between $3,000 and $7,500 depending on the scope of work.

Total Cost Estimation and Budgeting Tips

Here is a realistic cost range for a 800+ horsepower Hellcat build using a supercharger upgrade on a good used car:

  • Used Dodge Challenger Hellcat (2015–2023): $47,000–$58,000
  • Supercharger kit + fuel upgrades: $10,000–$15,000
  • Forged internals (pistons, rods, rings, bearings, machine work): $6,000–$10,000
  • Transmission torque converter + labor: $1,500–$3,000
  • Differential/axles: $2,500–$4,500
  • Suspension & cooling: $3,000–$5,000
  • Labor (engine build, install, dyno): $6,000–$10,000
  • Tuning (dyno time + remote tune): $1,000–$2,500

Total estimated range: $77,000 – $108,000 (including a used car). If you use a new Hellcat, add an extra $15,000–$25,000. This matches the original article’s estimate but adds more accuracy for internals and cooling. Many owners manage to hit 800 on a stock engine with just a pulley and tune for under $70,000 all-in, but reliability suffers. If you want to do it right and drive it hard, budget for at least $85,000–$95,000.

Conclusion

Building a reliable 800+ horsepower Dodge Challenger Hellcat is a serious investment of time and money. The three biggest cost categories are the base vehicle, forced induction and fuel system, and engine/drivetrain strengthening. Cutting corners on the short-block or cooling will cost you more in the long run. Start with a solid used Hellcat, choose a supercharger upgrade for simplicity, and never skip professional tuning. With careful planning and a realistic budget, you can own a street-legal monster that runs high nines and terrifies supercars. For more detailed build logs, check out the Hellcat.org forum or consult a shop like American Muscle for parts packages. Now go build that 800-horse dream car.