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MHP 139 NIGHTMARE Crate Engine
MHP 139 NIGHTMARE Crate Engine - Image 2
MHP 139 NIGHTMARE Crate Engine - Image 3

MHP 139 NIGHTMARE Crate Engine

$6,600.00 Original price was: $6,600.00.$5,999.00Current price is: $5,999.00.
In Stock
  • MHP 139 NIGHTMARE Crate Engine. Available with MSO which is equivalent to a title for an engine. 4.500″ Bore 4.375″ Stroke 172 Horsepower 161 Torque Dyno graph is with a D&D Big Bore and it’s a torque MONSTER with 160 foot pounds from roughly 4,000- 5,500 RPMS. With a larger Exhaust setup like our MHP Pro-Mod, Thunder Header or Burns Stainless you’d see some extra HP above 5,500 RPMS
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Description

The MHP 139 Nightmare Crate Engine from Moonshine Horsepower (MHP) is the ultimate high-performance drop-in beast for Milwaukee-Eight powered Harley-Davidson builds — delivering mind-bending torque and horsepower in a streetable package that lives up to its terrifying name.

Engineered for riders who demand extreme power without compromise, this 139 cubic inch (approximately 2280cc) crate engine features massive 4.500″ bore × 4.375″ stroke dimensions for explosive low- to mid-range grunt and impressive top-end pull. Rated at 172 horsepower and 161 ft-lbs of torque (with potential for even higher numbers — some tuned builds hit 173+ HP and 163+ ft-lbs on the dyno), it’s a torque monster that holds around 160 ft-lbs from roughly 4,000 to 5,500 RPM on a D&D Big Bore exhaust setup. Swap in a larger system like the MHP Pro-Mod, Thunder Header, or Burns Stainless, and you’ll unlock extra horsepower above 5,500 RPM for blistering acceleration.

Hand-built with premium American components, the Nightmare includes high-flow CNC-ported heads (often MHP Monster Heads with oversized valves), custom pistons, upgraded rods (Carrillo in many configs), reinforced flywheels (S&S), aggressive cam profiles (like the MHP 610), and precision internals designed for reliability under hard riding. The engine arrives as a complete crate ready for installation, and it’s available with MSO (Manufacturer’s Statement of Origin) — essentially a title for the engine — making registration and ownership straightforward in most areas.

Whether you’re transforming a bagger, Softail, or touring rig into a tire-shredding monster, the MHP 139 Nightmare turns your Harley into a nightmare for the competition. This isn’t just an upgrade — it’s domination on two wheels.

Key Specs:

  • Displacement: 139 ci
  • Bore x Stroke: 4.500″ x 4.375″
  • Horsepower: 172 HP
  • Torque: 161 ft-lbs (160+ ft-lbs flat from 4,000–5,500 RPM in tested configs)
  • Configuration: Milwaukee-Eight compatible crate engine
  • Includes: MSO documentation available

Perfect for:

  • Serious performance builds
  • Big-bore enthusiasts craving massive low-end torque
  • Riders who want proven dyno results and street manners