Inside The Tamiya MF-01X Fiat 131 Abarth Rally Car

Paul Onorato October 31, 2025 Stories

ABOUT THE REAL FIAT 131 ABARTH RALLY CAR

The storied history of the Fiat 131 Abarth Rally began with its highly anticipated global debut in 1976. This purpose-built racer quickly proved its formidable capabilities, clinching the World Rally Championship title an impressive three times throughout its career. Its roots lie in the popular, everyday Fiat 131 Mirafiori family sedan, which Abarth meticulously engineered into a rally weapon. During the 1976 and 1977 seasons, the car frequently campaigned in the memorable blue and yellow livery of the Fiat-owned oil brand, Olio Fiat—the exact decoration replicated by this stunning Tamiya RC assembly kit. The distinctive and alluring contours of the vehicle have been faithfully captured in the polycarbonate body shell, complete with separately molded pieces for the quad headlights, crucial spotlights, and the aerodynamic roof spoiler.

Inside The Tamiya MF-01X Fiat 131 Abarth Rally Car — This classic rally car is a perfect match for the highly capable MF-01X chassis.

A close-up on the front of the car, which has separate parts for light cases and fog lamps.

Dish wheels are paired with 60mm-diameter, 26mm width rally block tires.

The chunky overfenders are an important element of the car’s image, and the air intake cover is also depicted.

ABOUT THE TAMIYA MF-01X CHASSIS

The core of this rally platform is the Tamiya MF-01X chassis, a design optimized for competence across both tarmac and flat dirt tracks. Tamiya ensured its durability by utilizing a solid monocoque frame that cleverly integrates the gearboxes directly into its structure. This results in a chassis that is both extremely tough and compact.

A slimline three-piece monocoque forms the centerpiece of the MF-01X chassis, and the propeller shaft is positioned to the right.

The powerplant for Tamiya vehicles is typically a 540 brushed motor, though the Fiat 131 Abarth kit provides an enhanced Tamiya Torque Tuned motor. The motor is strategically placed in the rear, delivering power to the rear wheels, with a sturdy metal propeller shaft efficiently connecting it to the front gearbox. Reliable and robust gear differentials are employed in both the front and rear axles. A defining feature of the MF-01X is its modular construction; the chassis is split into three sections, allowing the central spacer to be changed to achieve three different wheelbases: short (210mm), middle (225mm), and long (239mm). For a balanced 4WD setup, the battery pack is centrally mounted, optimizing weight distribution. Standard four-wheel independent double wishbone suspension, controlled by friction shocks, ensures the necessary stability and control required for rally-style action.

TAMIYA FIAT 131 ABARTH SPECS

Item #58723
Scale: 1/10
Type: Build-up kit
Chassis Type: MF-01X
Length: 15.75 in. (400mm)
Width: 7.09 in. (180mm)
Wheelbase: 9.41 in. (239mm)
Chassis: ABS plastic monocoque frame
Drivetrain: Shaft-driven 4WD
Differential: 3 gear, bevel gear diffs
This image shows the double wishbone rear suspension with its coil sprung dampers.

Bearings: Metal and plastic bushings
Motor: 540 Torque-Tuned brushed
Speed control: Electronic speed control
Suspension: Lower H-links w/ front upper fixed links and rear upper adjustable links
Shocks: Molded plastic, friction type
Body material: Polycarbonate

REQUIRED TO COMPLETE

2-channel radio system
Steering servo
Battery pack
Battery charger
Polycarbonate & ABS Plastic Paint

6 WORTHWHILE TAMIYA HOP-UP OPTION PARTS TO CONSIDER

One of the many awesome features of Tamiya RC cars is significant assortment of Tamiya hop-up option parts that each of the cars have available to it. Following are six that we feel are most worthwhile to furth boost the performance, speed and durability of the Tamiya MF-01X Fiat 131 Abarth rally car kit.

Tamiya M-05 Ball Differential Set — #54194

The MF-01X chassis comes equipped from the factory with bevel gear differentials. While functional, serious racers seeking a competitive edge will want to upgrade to the optional Tamiya M-05 Ball Differential Set. This hop-up significantly improves both stability and traction, particularly under challenging conditions. Unlike the stock gear differential, the ball differential offers virtually zero backlash, ensuring a much smoother and more precise power delivery. This refined control is especially noticeable in tight cornering situations, giving you consistent traction when driving over slick or unpredictable surfaces. Be aware that installing this unit requires a fair amount of chassis teardown; if you are also upgrading the car’s bushings to full ball bearings, it makes perfect sense to perform both essential modifications at the same time.

Tamiya MF-01X Aluminum L Wheelbase Propeller shaft — #54673

While some might mistakenly view this optional propeller shaft as purely a cosmetic upgrade, its benefits extend far beyond aesthetics. True, it arrives beautifully anodized in Tamiya blue and features a crisp white logo, providing a sharp visual pop to the chassis. However, the true advantage lies in its material: this shaft is crafted from lightweight aluminum, weighing approximately one-third the mass of the heavy stock steel shaft. Reducing the rotating mass within the drivetrain significantly improves efficiency and results in noticeably more responsive throttle input. Crucially, given the MF-01X chassis’s ability to be built in three wheelbase lengths—short, medium, and long—Tamiya offers three corresponding optional aluminum propeller shaft lengths to ensure a perfect fit regardless of your chosen chassis configuration. The Abarth utilizes the long wheelbase and requires this specific optional propeller shaft.

Tamiya MF-01X Ball Bearing Set — # 54643

To keep kit costs accessible, Tamiya supplies all MF-01X models with a combination of plastic and metal bushings for the initial build. While these bushings are adequate for starting out, maximizing the performance of your MF-01X requires upgrading to a full set of metal ball bearings. This comprehensive set replaces every stock bushing with high-quality, super-smooth bearings. The immediate benefit is a dramatic reduction in drivetrain friction, which translates directly into increased efficiency and more overall speed. Furthermore, installing ball bearings significantly reduces wear and tear on critical rotating components, helping to extend the lifespan and reliability of your chassis. This is one of the most fundamental and cost-effective performance upgrades available.

Tamiya MF-01X Aluminum Motor Mount — # 54660

For owners planning to move beyond the stock power unit and install a hotter, higher-performance motor, the MF-01X aluminum motor mount is a must-have upgrade. The chassis initially uses a molded plastic plate for motor attachment, which is sufficient for the stock motor. However, upgrading to this precision-machined aluminum mount provides a rigid and secure foundation that a more powerful motor demands. As an additional critical benefit, metal construction dramatically improves heat dissipation, drawing heat away from the motor and helping it maintain cooler, more efficient operating temperatures. Finally, this piece adds visual appeal; the motor mount is finished in a brilliant blue anodizing, which creates a sharp vertical blue stripe across the rear gearbox, adding instant style to your chassis

Tamiya Double Cardan Joint Shaft — # 42300

Tamiya offers a particularly ingenious drivetrain upgrade in the form of these specialized Double Cardan Universal Shafts. While similar in function to standard universal drive shafts, the key feature here is the double-joint design. The primary concept behind this advanced articulation is the elimination of the binding and vibration often associated with the standard dogbone setup, which leads to a smoother power delivery than even typical universal shafts. The practical result for the driver is immediately noticeable: you gain improved steering response while accelerating and a far better, less restricted suspension action throughout the full range of travel.

Tamiya M-Chassis Aluminum Damper Set — # 54000

The MF-01X is designed for easy entry into RC, and its simple, virtually maintenance-free friction shocks reflect this goal. However, these stock units are known to make the car bouncy and difficult to control when running off-road. To truly unlock the platform’s potential, you must upgrade to a full set of oil-filled dampers, such as the Tamiya M-Chassis Aluminum Damper Set. These are not ordinary units; they are high-performance shocks featuring slick black-coated cylinders with mirror-smooth interiors, along with fluorine resin pistons and soft silicone O-rings to minimize friction and prevent oil leakage. They also include threaded bodies for precise spring tension adjustment and come with three different spring rates.

For more information about Tamiya products, visit: TAMIYA