1971-73 Cougar Q-Code 351 Cleveland Cobra Jet Option

1972 Mercury Cougar XR-7 Convertible 351CJ

351-cobra-jet-150The Q-code “351 Cobra Jet” version of the Cleveland was produced from May 1971 through the 1974 model year. It was a low-compression design that included the following:

  • Open-chamber “4V” heads
  • Special intake manifold
  • Special hi-lift long duration hydraulic camshaft
  • Special valve springs and dampers
  • A 715 CFM 4300-D Motocraft Carburetor
  • 4-bolt main bearing caps
  • Specially balanced crank shaft for high RPM
  • Special high RPM valve springs
  • Large inertia vibration dampner
  • 2½-inch exhaust outlets
  • 262 net HP

1971 Mercury Cougar Q-Code 351-4V w/ the 351-CJ Performance Group Option

According to Kevin Marti’s book Cougar…by the Numbers, there was one (1) 1971 Cougar produced with the Q-code engine and it had an automatic transmission.

It had 280 net HP.

Little is known about this Cougar.


1972 Mercury Cougar Q-Code 351-4V w/ the 351-CJ Performance Group Option

Changes from 1971 M-code to 1972 Q-code Cobra Jet cars included the following :

1972 Mercury Cougar

  • 351-2v: 164 net  HP
    • 351 -4v:  262  net HP
    • 351- CJ: 266 net HP

CJ Performance Group Package included the following:

  • 10¼” stall converter
  • Upgraded dual exhaust
  • Competition suspension
  • F70-14 tires

1972 last year for the GT package.


The 351-4V Cobra Jet engine was also available with the 351-CJ Performance Group Option.

Optional for all Cougar models: $162.90 for all models except GT or $105.88 with GT Option Package.

Cobra-Jet Performance Group Option included the following:

  • 351 4V (Cleveland) Engine
  • 266 net horsepower rating
  • Low Restriction Dual Exhaust with a throaty growl (Sporty Exhaust)
  • Competition Suspension with rear stabilizer bar
  • F70 x 14 White Sidewall Tires
  • Available with 4-speed manual transmission with Hurst Shifter or Select Shift automatic transmission.
  • When the CJ engine is teamed with the automatic transmission, a smaller 10¼-inch torque converter is used to give a livelier and more sporty shift feel.

New Options for 1972


  1. 351-CJ Performance Group – Includes the new regular fuel 351-CJ performance engine with “Sporty” dual exhausts, competition suspension and F70 x 14 WSW belted tires. Available on all models with optional 4-speed manual or SelectShift transmission. Special engine performance / durability components include:
    • Specially balanced crankshaft for higher rpms
    • Four-bolt main bearing caps
    • Improved performance high lift camshaft
    • Large capacity 4-bbl carburetor
    • Special high rpm valve springs
    • Large inertia member vibration damper
    • 2½-inch diameter exhause outlets
    • 10¼-inch SelectShift transmission converter
  2. 351-4V V-8 Engine – Same basic engine as in the 351-CJ Performance Group except has a “quiet” dual exhaust and uses a 12-inch converter with SelectShift instead of the 10¼-inch converter used with the 351-CJ and SelectShift. Replaces the 351-4V premium fuel engine used in 1971. Available only with optional SelectShift transmission.
  3. Glamour Metallic Paint – Available in Ivy Glamour Metallic and Gold Glamour Metallic, this paint has extra metal flake for a lustrous righ appearance.
  4. Protective black vinyl bodyside molding with bright accents.

1973 Mercury Cougar Q-Code 351-CJ

In 1973, the 351-4V was dropped. the only two choices were the 351-CJ or 351-2V.

The 351-CJ engine was $74.70 over the standard 351-2V engine.

It came with the following options:

  • 10¼-inch converter with Select Shift transmission
  • Higher rate springs
  • Heavy duty shock absorbers
  • Large diameter front and rear stabilzer bars


Some text from The Big Book: Mercury Cougar: The Classic Years 1967-1973


1973 Mercury Cougar 351-CJ Details


  • 351-CJ: 266 net HP (no 4v designation )
  • CJ Performance Group Package N/A
  • Both Standard and XR-7 models, hard top and convertible, were available with the Cobra Jet Package upgrade
  • All colors and trim options were also available
  • 3 speed Manuel Transmission N/A on Q-code equipped cars

Q-code engine option available with higher axle ratio 3.25:1 open was standard.

Competition suspension (included heavier front sway bar and rear sway bar, along with different springs and shocks)

Dual sport mirrors and hood scoop were available for Standard model Cougars only. No GT option with XR-7.

GT badging, cooling package, tach, rimblow wheel, E78-14 WSW tires, steel styled wheels, and black instrument panel were available.


Production Numbers



Total # of Mercury Cougars: 62,864

Total # of 351-CJ: 1



  • Hardtop : 1


Total # of Mercury Cougars: 53,702

Total # of 351-CJ: 3,560



  • Hardtop Automatic: 500
  • Hardtop 4-Speed: 66
    • 65 of the Hardtops above came equipped with the GT package
  • Convertible Automatic: 64
  • Convertible 4-Speed: 5


(GT Package not available)

  • Hardtop Automatic: 2,401
  • Hardtop 4-Speed: 156
  • Convertible Automatic: 336
  • Convertible 4-Speed: 32


Total # of Mercury Cougars: 60,628

Total # of 351-CJ: 3,288


GT Package not availble in 1973


  • Hardtop Automatic: 220
  • Hardtop 4-Speed: 93
  • Convertible Automatic: 40
  • Convertible 4-Speed: 14


  • Hardtop Automatic: 2,225
  • Hardtop 4-Speed: 260
  • Convertible Automatic: 372
  • Convertible 4-Speed: 64

Data from Cougar . . . by the Number (1967-1973)


Build Sheets


Marti Reports


Colors of the 1971-73 Mercury Cougar 351 Cobra Jet (Q-Code)

Paint Code: 2B | Ditzler #: 2296 | Paint Color: Bright Red


Paint Code: 4C | Ditzler #: 2362 | Paint Color: Ivy Glamour Poly.


Paint Code: 4N | Ditzler #: 2507 | Paint Color: Medium Aqua


Paint Code: 4Q | Ditzler #: 2291 | Paint Color: Dark Green Poly.


Paint Code: 5A | Ditzler #: 2287 | Paint Color: Light Pewter Poly.


Paint Code: 6E | Ditzler #: 2414 | Paint Color: Medium Bright Yellow


Paint Code: 6F | Ditzler #: 2415 | Paint Color: Gold Glamour Poly.


Paint Code: 9A | Ditzler #: 8378 | Paint Color: White


Paint Code: <blank> | Ditzler #: Special Paint | Paint Color: Black