Factory Five Racing (FFR)

Post image

This report examines Factory Five Racing’s evolution in the component car sector, emphasizing how advanced chassis engineering, digitized manufacturing, and customer-supplied powertrains have redefined the kit-car industry. It compares the Mk4, Mk5, and 289 USRRC platforms while evaluating the broader economic and structural implications of FFR’s manufacturing model.

1.0 Introduction

Factory Five Racing pioneered a new alternative for automotive enthusiasts by merging modern CAD/CAM engineering with customer-installed mechanical systems. This approach bridged the gap between production vehicles and classic restorations, offering a performance-driven, cost-controlled platform.

###1. Platform Overview
Factory Five Racing (FFR) produces component vehicles using a hybrid manufacturing approach where the factory provides the engineered chassis and structural components while the end-user provides the mechanical powertrain and finishing systems.

Factory-Supplied Components

  • Chassis / frame (welded steel)
  • Composite body shell
  • Suspension geometry and mounting structure
  • Interior aluminum panels

User-Supplied Components

  • Engine and transmission
  • Rear-end or IRS assembly
  • Brake components
  • Wiring and ancillary systems

Performance Metric:
A typical Mk4 Roadster (~2,300 lbs) equipped with a Ford Coyote engine achieves a power-to-weight ratio superior to a Ferrari 458.

2. Complete Model Portfolio

The table below includes current Factory Five Racing models along with typical kit costs. Prices represent the chassis/body kit only and do not include engine, transmission or paint.

Model Designation Category Chassis Type Status Cost (US$)
Mk4 Roadster Roadster 4" Round-Tube Ladder Production US$14,000–US$19,000
Mk5 Roadster Roadster Digitally Optimized 4" Ladder Production US$15,000–US$20,000
289 USRRC / FIA Roadster 4" Ladder with FIA Outriggers Production US$14,000–US$18,000
Type 65 Coupe GT Coupe Space Frame with Cage Production (Gen 3) US$22,000–US$28,000
'33 Hot Rod Hot Rod Space Frame (Cantilever) Production (Gen 2) US$20,000–US$25,000
'35 Hot Rod Truck Street Truck Space Frame (Cantilever) Production US$22,000–US$26,000
F9R Supercar Carbon/Composite Space Frame Production US$25,000–US$32,000
XTF Off-Road Truck Long-Travel Space Frame Production US$15,000–US$22,000
818 S/R/C Sport Compact Square-Tube Space Frame Legacy / Special Order US$12,000–US$18,000
GTM Supercar C5-Based Mid-Engine Space Frame Legacy / Special Order US$25,000–US$35,000
Challenge Series Race Car Spec Racer Tube Frame Legacy US$10,000–US$15,000

3. Roadster Model Specifications

3.1 Mk4 Roadster

The Mk4 Roadster represents the quintessential Factory Five platform, capturing the spirit of the 1966 427 S/C while incorporating modern engineering improvements.

Key Features

  • Chassis: 4-inch round-tube ladder frame with backbone reinforcement for increased torsional rigidity
  • Suspension Compatibility: Accommodates 4-Link, 3-Link or IRS configurations
  • Bodywork: Wide rear haunches, period-correct hood scoop, deep side vents and flares supporting up to 315 mm rear tires
  • Interior: Traditional compact cockpit, vintage-style dashboard layout, aluminum interior paneling
  • Engine Bay: Supports carbureted or EFI small-block and big-block V8s; allows large-displacement engines without significant modification
  • Steering and Brakes: Manual or power-assisted options depending on donor or chosen components
  • Ergonomics: Suited for medium-sized drivers; narrower footbox compared to Mk5

Driving Impressions

The Mk4 delivers one of the most authentic vintage driving experiences in the FFR lineup. On the road, the chassis communicates every nuance of the pavement—small vibrations, tire slip, surface transitions—making it extremely engaging. Acceleration is immediate and forceful, especially with a 427W or stroker motor; the car surges forward with a sense of urgency typical of 60s big-block racers.

Steering is quick and unfiltered, requiring precise input at speed. The high torque and short wheelbase create a lively rear end, demanding a disciplined throttle foot when exiting corners. The wind buffeting and engine noise heighten the drama, making the car feel alive at any speed. The Mk4 excels as a weekend performance machine, offering a visceral, mechanical, hands-on driving feel that rewards skilled drivers but can intimidate the inexperienced. High-speed stability is limited compared to the Mk5 due to vintage aerodynamic lift characteristics.

3.2 Mk5 Roadster

The Mk5 is Factory Five’s modern evolution of the Roadster platform—digitally redesigned for improved fitment, ergonomics, and high-power engine compatibility.

Key Features

  • Chassis: Updated 4-inch ladder frame with reprofiled vertical rails and widened footboxes
  • Structural Refinements: Reinforced cowl section and improved load distribution increase chassis stiffness
  • Body: 100% symmetrical CAD-modeled body mold with cleaner panel transitions, tighter wheel arch radii and integrated splitter mounting points
  • Ergonomics: Expanded cockpit width (+2.5 inches), deeper footwells, improved pedal spacing
  • Engine Fitment: Designed for Ford Coyote and Godzilla engines without compromising legroom; also supports LS platforms
  • Panels: CNC pre-cut and pre-drilled aluminum panels reduce build time
  • Steering / Suspension: Enhanced geometry precision; optimized for IRS applications

Driving Impressions

The Mk5 feels significantly more refined than previous generations. At low speeds, the chassis feels tighter with fewer vibrations, and the improved ergonomics create a more relaxed driving posture. On the highway, it tracks straighter, with noticeably reduced wind instability and improved aero balance.

Cornering behavior is more predictable thanks to the stiffer structure and improved suspension geometry. Inputs feel smoother and more progressive, and mid-corner stability is superior to the Mk4. With a Coyote or Godzilla, power delivery is crisp and linear, making the Mk5 exceptionally responsive under throttle. High-speed behavior (70+ mph) is stable and confidence-inspiring, especially when equipped with a front splitter.

On the track, the Mk5’s ability to accept high-grip tires, IRS, and modern engines gives it a strong performance advantage—better braking stability, reduced bump steer, and more controllable oversteer. Overall, it feels like a modern interpretation of the classic Roadster: powerful, balanced and surprisingly composed for a lightweight open-top car.

3.3 289 USRRC / FIA

The 289 USRRC / FIA model captures the lighter, more agile personality of the early 1960s racing Cobras, emphasizing finesse over brute power.

Key Features

  • Body Options: Slabside or FIA competition body with small flares and classic proportions
  • Chassis: Narrow-body outriggers based on the Mk4 but optimized for smaller bodywork
  • Period Details: External trunk hinges, forward-leaning single roll bar, underbody exhaust routing
  • Weight Characteristics: Lighter overall compared to Mk4/Mk5 due to narrower bodywork and smaller engines
  • Engine Fitment: Optimized for small-block 289–302 engines; supports carbureted or vintage EFI systems
  • Handling: Lower polar inertia due to reduced body width and lighter front-end mass
  • Cabin: Classic narrow cockpit with vintage-style seating position and minimal driver aids

Driving Impressions

The 289 USRRC delivers the purest vintage driving experience in the FFR lineup. With a small-block engine, throttle response is lighter and more manageable, making the car easier to balance and rotate through corners. The reduced weight provides quick turn-in and a nimble, responsive feel reminiscent of classic 1960s sports racers.

Compared to the Mk4 and Mk5, the 289 feels more delicate and precise. Mid-corner behavior rewards smooth steering and throttle modulation, allowing experienced drivers to maintain high momentum. Braking stability is strong thanks to the lighter front end, and the car exhibits less tendency to overwhelm the rear tires.

The sound, vibration and tactile sensations are more vintage: more mechanical whine, more rev-happy character, tighter cabin acoustics. On winding mountain roads or technical circuits, the 289 feels like a well-balanced race tool—engaging, controllable and incredibly rewarding for precise driving. It is the connoisseur’s Roadster, ideal for enthusiasts who value handling finesse over raw power.

3.4 Roadster Comparison Matrix

Feature Mk4 Roadster Mk5 Roadster 289 USRRC / FIA
Visual Style Aggressive, wide hips Clean, symmetrical Vintage, narrow
Cockpit Space Standard Expanded (+2.5") Traditional narrow cockpit
Ideal Engine 427W / Coyote Coyote / Godzilla / LS 289 / 302 / 347
Engine Bay Large, flexible Optimized for wide OHC engines Small-block optimized
Body Features Deep flares, side vents Tighter radii, splitter options External hinges, FIA details
Aero Characteristics High lift at speed Improved stability Vintage lift
Driving Character Raw, high-torque, dramatic Balanced, modern-feel, stable Light, agile, vintage-race
Best For Enthusiasts seeking authentic 427-style aggression Drivers wanting modern usability + classic looks Purists seeking 1960s FIA handling feel

4. Assembly Procedures

Phase 1: Logistics & Inventory

  • Shipment: Stewart Transport or pickup
  • Verify frame ID with MSO
  • Inventory 20–30 boxes; document backorders immediately

Phase 2: Mechanical Preparation

  • Strip donor vehicle (if applicable)
  • Retain engine, transmission, spindles, rear end, brakes
  • Clean and paint donor parts
  • Mk5 note: Completion Pack eliminates need for donor front spindles

Phase 3: Chassis Assembly

Aluminum Paneling

  • Drill, cleco, and rivet floor, firewall, trunk
  • Mk5 panels are CNC pre-drilled
  • Coat panels for corrosion prevention
  • Required Tool: Pneumatic rivet gun

Suspension & Powertrain

  • Install control arms, differential
  • Mount engine and transmission

Phase 4: Go-Kart Validation

Checklist:

  • Engine starts and idles
  • No coolant, oil, or brake leaks
  • Steering geometry validated (bump-steer check)
  • Electrical harness continuity verified

Phase 5: Body Fitment

  • Sun-cure (“buck”) body to stabilize resin
  • Trim mold lines
  • Adjust hood, doors, trunk gaps
  • 289 Note: Align external hinges to avoid paint interference

5. Engineering: Chassis & Suspension

5.1 Rear Suspension Options

4-Link (Solid Axle)

  • Upper + lower arms
  • Can bind; best for drag racing

3-Link (Solid Axle)

  • Central upper link + Panhard bar
  • Eliminates bind; superior track performance

IRS (Independent)

  • Uses 2015+ Mustang Super 8.8
  • Best compliance and ride quality

6. Powertrain Integration

6.1 Engine Options (with Costs)

  • Ford Windsor (302 / 351)

    • Ideal for Mk4 and 289 USRRC builds
    • Simple wiring, period-correct appearance
    • Cost: US$4,500–US$9,000 (crate)
    • Budget rebuilt option: US$2,500–US$4,000

  • Ford Coyote 5.0L

    • High horsepower and modern reliability
    • Best match for Mk5 due to wider block dimensions
    • Cost: US$7,800–US$12,000 (Gen 3 or Gen 4 crate)
    • Control Pack: US$1,800–US$2,200

  • Ford Godzilla 7.3L

    • Extremely high torque
    • Fits the Mk5 without chassis modification
    • Cost: US$8,000–US$10,500 (crate long block)
    • Control Pack: US$2,300–US$2,700

  • GM LS Series

    • Cost-effective, compact and tunable
    • Fits Mk5, GTM and 818
    • Cost:
      • LS3 crate: US$7,500–US$9,500
      • 5.3L truck engine (used): US$1,200–US$2,000

6.2 Transmission Options (with Costs)

  • Tremec TKX (5-speed)

    • Slim, modern drivetrain solution
    • Suitable for Windsor and Coyote engines
    • Cost: US$2,900–US$3,200
    • Clutch and flywheel pack: US$900–US$1,400

  • Tremec T56 Magnum (6-speed)

    • Heavy-duty performance transmission
    • Mk5 tunnel fits without modification; Mk4 may need trimming
    • Cost: US$3,900–US$4,700
    • Clutch hydraulics and flywheel: US$1,200–US$1,600

  • Automatic transmissions

    • Examples: 6R80 (Ford), 4L60E / 6L80 (GM)
    • Costs:
      • Used pull-out: US$1,000–US$2,500
      • Rebuilt performance unit: US$3,500–US$5,500
    • Controllers: US$1,200–US$2,000

6.3 Drivetrain and Supporting Systems (with Costs)

  • Driveshaft: US$350–US$600
  • Cooling system (radiator, fan, hoses): US$600–US$1,200
  • Headers and exhaust: US$700–US$1,500
  • Fuel system (pump, lines, tank modifications): US$300–US$700
  • Engine mounts and brackets: US$150–US$400

6.4 Total Powertrain Budget

Budget build (Windsor + TKX + used parts): US$7,000–US$12,000
Mid-tier build (Coyote + TKX): US$12,000–US$18,000
High-end build (Coyote or Godzilla + T56 + new components): US$17,000–US$24,000+

7. Legal & Homologation

  • Classified as a Specially Constructed Vehicle
  • California SB100 allows smog-exempt 1965 registration
  • State-issued VIN must be permanently riveted to chassis

Factory Five Racing