Stage 5 Harbor Freight Predator Equipped with a Turbo and EFI is the Ultimate Go-Kart Engine.

      Red Beard Garage on YouTube

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      I’ve reached a stage in my life where Harbor Freight Predators seem more fascinating than LS engines. While they can’t compete with GM’s affordable performance favorite, you don't see them being swapped into every classic truck and hot rod (aside from the occasional Honda Insight or Chinese UTV). Then there’s Red Beard’s Garage on YouTube, which has constructed a 670cc Predator, outfitted with a turbo, billet pistons and connecting rods, electronic fuel injection, and much more. How could you not be intrigued?

      This guy works on various small engines. You can watch him tinker with single-seater go-karts, like the Yerfdog Spiderbox—what a unique name—alongside modified pit bikes. However, this V-twin project might be the most ambitious he's undertaken in terms of genuine speed enhancements.

      Numerous aftermarket companies offer support for the 670cc Predator, giving Red Beard’s Garage a wealth of parts to pick from. Alongside a turbo he purchased on Amazon, typically used for powering Bobcat skid steers and Doosan forklifts, he’s equipped with a well-known Holley Sniper EFI, as well as billet rods and pistons, a billet flywheel, roller rocker arms, electronic ignition, and an upgraded 507 camshaft from Performance Machine and Design. The head modifications were handled by Beckwith Performance, a friend of the shop that focuses on Predators, plus Briggs and Stratton and Kohler engines.

      Considering a stock 22-horsepower Predator 670 costs $949, the price of these components can easily exceed that. Luckily for Red Beard, he acquired many of these upgraded parts at a lower cost since they were used. You might get fortunate and uncover similar bargains, but remember—this is not as budget-friendly as adjusting the carburetor on your minibike.

      What any DIY enthusiast will value is that the host explains every aspect of the process, slightly sped up with on-screen captions detailing the tools he's using. The calm voice narration is easy to follow, and combined with steady camera work, it’s enjoyable to watch.

      Red Beard intends to run 12 psi of boost through this engine, which should provide a significant performance increase. It’s still uncertain how much power it will generate. He already has a supercharged Predator-powered go-kart that runs at 14 psi, and it’s quite lively. Once the turbo build is complete, he plans to race the two against each other to see which one comes out on top.

      Regardless, boosted Harbor Freight engines are definitely something I support.

      Stage 5 670cc Turbo EFI Engine Build

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