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Ford R125 Mustang Pairs 1966 Fastback With 360-HP V8

Red 1966 Ford Mustang 2+2 Fastback photographed outdoors at a car show
Archive/illustrative image: stock-bodied 1966 Ford Mustang 2+2 Fastback, not Ford Racing’s R125 show car. Photo by Jeremy via Wikimedia Commons, CC BY 2.0.

Ford Racing has turned a 1966 Mustang Fastback into the R125, a SEMA show car powered by a currently listed 347-cubic-inch crate V8 rated at 360 horsepower and 400 lb-ft of torque. The build celebrates 125 years since Henry Ford’s 1901 Sweepstakes race victory, but it is also a practical catalog demonstration rather than a new Mustang trim or complete vehicle customers can order.

The R125 will appear at the 2026 SEMA Show in Las Vegas, which runs November 3–6. Ford says the car was assembled around Ford Racing Parts and supporting components from partner companies to show how a classic Mustang can combine period character with modern fuel injection, a contemporary five-speed transmission and serviceable performance hardware.

Ford R125 Mustang specifications

ComponentR125 specificationWhat buyers should know
Base vehicle1966 Ford Mustang 2+2 FastbackComplete R125 is a show build, not a production model
Engine347-cu-in Ford Racing X2347 small-block V8Catalog crate engine; installation parts and labor are separate
Output360 hp and 400 lb-ftFord Racing rating for the crate engine
Fuel systemEdelbrock Pro-Flo 4 XT electronic fuel injectionRequires vehicle-specific integration and tuning
TransmissionTremec TKX-600 five-speed manualNot included with the engine
Engine catalog price$13,750 MSRP as listed by Ford RacingPrice is for the crate engine, not the R125 build
Ford Racing’s published specifications; prices and availability should be confirmed before ordering.

The distinction between the engine and the finished car matters. Ford’s November 2 story says the parts used in the R125 are available through Ford Racing Parts, but it does not publish a package price, build sheet with every component, production quantity or ordering program for a complete R125. The $13,750 figure is the catalog MSRP for the X2347 EFI crate engine at the time of publication.

A modern-production pushrod V8

Ford Racing identifies the engine as a 302-based small-block enlarged to 347 cubic inches. The published recipe uses a Boss 302 8.2-inch-deck block, a forged-steel crankshaft, forged I-beam connecting rods, forged Mahle pistons and aluminum cylinder heads with 64-cc combustion chambers.

The bore measures 4.030 inches and the stroke is 3.400 inches. Compression is 9.6:1, Ford recommends premium unleaded fuel and lists 6,000 rpm as the maximum recommended engine speed. Edelbrock’s electronic fuel injection replaces a traditional carburetor, while an MSD billet distributor and Ford Racing plug wires retain the familiar small-block ignition layout.

Those are Ford Racing’s catalog specifications, not independently measured output from the completed R125. Ford has not published a chassis-dyno result, vehicle weight, acceleration time, brake package or track performance figure for the show car. The 360-hp and 400-lb-ft numbers therefore describe the crate engine rating rather than independently verified performance at the rear wheels.

Why Ford chose the TKX-600 transmission

The five-speed Tremec TKX-600 is more compact than the earlier TKO design and is intended to improve shift quality and durability in performance applications. Ford presents the pairing as a way to add modern drivability without replacing the classic Mustang’s basic front-engine, rear-drive character.

Installation is not automatically a bolt-in weekend job. The crate-engine catalog notes that buyers must account for a neutral-balance flywheel, cooling hardware, accessory drives, exhaust, fuel delivery, wiring, calibration and the correct oil-pan arrangement. Transmission fitment, clutch hydraulics, driveshaft length, crossmember placement and rear-axle compatibility also depend on the individual car.

The visible parts are meant to be serviceable

Ford highlights two-piece valve covers with interchangeable top designs, captured O-ring seals and integrated spark-plug-wire looms. The feature sounds cosmetic, but the removable top and reusable sealing approach are intended to simplify customization and service.

The R125’s broader styling, chassis and interior changes are less fully documented in Ford’s initial release. That limits what can be stated confidently about the complete car. It is safest to treat the R125 as a rolling parts showcase, not a fully specified restomod kit with a single price or guaranteed performance outcome.

How the R125 differs from a new Mustang upgrade

This project starts with a 60-year-old chassis and a pushrod small-block, unlike current Mustang-based performance cars. Chiefs Review’s guide to the 2026 Shelby Super Snake covers a modern Mustang package with a supercharged V8 and a published complete-vehicle pathway. The R125 is a one-off demonstration that requires a donor car, fabrication and a much longer parts list.

Ford has also been expanding dealer-supported personalization in other parts of its lineup. The Bronco ORV package, for example, has a defined price and fitment range. Ford has not announced comparable package pricing or eligibility for the R125.

The R125 is one of several manufacturer-backed custom builds arriving for SEMA. Chiefs Review has separately reported on Nissan’s Frontier RONIN, Pathfinder XE‑V6 and Armada Jungle Patrol concepts, which likewise mix purchasable parts with prototypes and one-off fabrication.

What is confirmed—and what is not

  • The R125 is based on a 1966 Mustang Fastback.
  • Its Ford Racing 347-cu-in crate engine is rated at 360 hp and 400 lb-ft.
  • The engine uses a Boss block, aluminum heads and Edelbrock electronic fuel injection.
  • A Tremec TKX-600 five-speed sends power to the rear wheels.
  • The X2347 EFI crate engine is listed at $13,750 MSRP.
  • Ford has not announced a complete R125 kit, sale price or production run.
  • No independent performance testing or complete vehicle specification has been published.

Featured image: A stock-bodied 1966 Ford Mustang 2+2 Fastback photographed in Australia in January 2016. This is an archive/illustrative photo of the donor-model type, not Ford Racing’s R125 show car. Photo by Jeremy via Wikimedia Commons, licensed under CC BY 2.0; source file. No changes were made other than WordPress image scaling.

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