A 6.2-liter Hellcrate Redeye supercharged Hemi, ordered off the shelf for about $21,000, arrived at MPR Racing Engines in Florida asking for mercy, its pistons melted, tuning and fuel delivery were out of whack. The factory specs of 807 HP and 717 lb-ft were no longer enough. That crate engine, directly tied to the Demon lineage, was ripe for a brutal evolution.
Instead of a repair to stock form, MPR decided to go big. They installed a stroker crank from Manley to boost displacement, swapped in CP forged pistons, H-beam connecting rods, and reworked valve timing with a custom Comp Cams grind. The blower got an upgrade too: a larger displacement Whipple unit replaced the stock supercharger. All told, the overhaul aims for a target of 1,300–1,400 HP on premium pump gas.
It’s a lesson in how one gives “crate engine” a whole new meaning. What started as a plug-and-play Hemi metamorphosed into a finely balanced monster: block machining to true lines, precision component fitting, and bespoke tuning. MPR warns that in a one-off build like this, supporting systems (fueling, cooling, etc.) often lag, which is exactly what triggered the engine’s initial meltdown.
The result? A crate engine once content with factory figures now aims at more than 1,300 HP reliably, hitting the 1,400 HP threshold under ideal conditions. That’s enough to push a capable street truck toward 8-second quarter miles, though this particular build will likely remain more showpiece than drag warhead.
Putting this kind of power into a street truck is audacious: the chassis, drivetrain, and controls must be coaxed not to revolt. But that’s the point. It’s not about sensible horsepower. It’s about bending reality, testing engineering limits, and making a crate engine into something legendary. In a world where crate engines are praised for bolt-on upgrades, this version throws that out the window, redefining what “plug and play” means.
