How Much Power Does Our 7.3L Godzilla Mustang Make?!

How much power does a 7.3L Ford Godzilla make in a 1965 Mustang Fastback? We’re taking it to the dyno to find out! After months of fabrication, wiring, and customization, our 1965 Ford Mustang Fastback finally has a new heartbeat: a swapped 7.3L Ford Godzilla V8. After getting the Mustang fired up for the first time in the previous episode, we headed to New Haven, Connecticut, to visit Scott “Scottie Wheels” MacDonald and put the car on his high-end hub dyno. Scottie is well known throughout the Northeast performance scene for his tuning expertise, particularly when it comes to EFI engine setups. With the Mustang strapped to the dyno, it was time to find out what this big-inch Ford could actually put down. And the numbers started getting interesting very quickly. Even Scottie was surprised by how much power the 7.3L Godzilla was making once the tune was fully dialed in. Presented by POR-15 @POR15videos this Mustang is running a seriously upgraded Godzilla V8 featuring a MAST Motorsports hot camshaft and CNC-ported heads, Holley intake, Holley Terminator X engine management, and a Lunar Outlaw Garage custom intake. The rest of the build includes an American Autowire Classic Update Series wiring harness, U.S. Radiator Triple Flow Down Flow Radiator, Toploader four-speed, Hurst V-Gate shifter, and a thoroughly upgraded Ford 9-inch rear end. Before we could make it to the dyno, we also had to replace a burnt aftermarket under-dash wiring harness with the American Autowire system, get the engine running, establish a base tune, and make some test laps around the parking lot. Now comes the big question: HOW MUCH POWER DOES THIS GODZILLA MAKE? 500 HP? 525 HP? 550 HP? 575 HP? Or does something break before we get there? Watch until the end for the final dyno numbers! 🔧 In This Episode: 7.3L Ford Godzilla dyno testing 1965 Mustang Fastback engine swap Final engine tuning Horsepower and torque numbers Scott “Scottie Wheels” MacDonald tuning Hub dyno testing MAST Motorsports hot camshaft MAST CNC-ported heads Holley intake Holley Terminator X Lunar Outlaw Garage custom intake American Autowire Classic Update Series U.S. Radiator Triple Flow Down Flow Radiator Toploader 4-speed transmission Hurst V-Gate shifter Upgraded Ford 9-inch rear end First startup and test drive 💬 MAKE YOUR PREDICTION Before watching the dyno pulls, what do you think this 7.3L Godzilla will make at the wheels? 🔥 Drop your horsepower AND torque prediction in the comments! 🔗 Build & Sponsor Links: POR-15: https://www.por15.com U.S. Radiator: https://www.usradiator.com American Autowire: https://americanautowire.com/ MAST Motorsports: https://www.mastmotorsports.com Holley: https://www.holley.com Lunar Outlaw Garage: https://lunaroutlaw.com/ Special Thanks: Scottiewheels Racing: https://scottiewheelsracing.com/ 🏁 MORE FROM HEMMINGS Subscribe to Hemmings for more classic car builds, engine swaps, project cars, restorations, muscle cars, performance upgrades, and automotive how-to videos. #FordGodzilla #Mustang #EngineSwap #Hemmings #POR15 #Holley #MASTMotorsports #AmericanAutowire #LunarOutlawGarage