Ford Mustang · 1971

Boss 351

The last Boss of the first generation, sold for 1971 only, with a 330 hp high-output 351 Cleveland.

The story

For 1971 the Boss 302 and Boss 429 were gone, and the Boss 351 took their place.12

It lasted one year. For 1972 the Boss models were dropped, and a lower-compression 351 HO took over as the top engine.34

How to spot a Boss 351

Only a 1971

There was no Boss 351 for 1972, so a Boss 351 in this body is a 1971.345

A painted hood with working scoops

The hood is painted black or argent and carries working ram-air scoops.12

Boss 351 stripes

Body-side stripes and Boss 351 lettering identify it.12

Chrome bumper

The Boss 351 came with a chrome front bumper as standard, with a body-colored one as an option, and the sport-lamp grille.24

Production by year

How many Boss 351s were built each model year.

1971
1,806
As a table, with notes
YearBuiltNote
19711,80616

Engines

The letter is the engine code in the VIN.

YearsCodeEngineRated
1971R351 cu in Cleveland V8, 4-barrel, Boss (high output)330 hp126

Where the sources disagree

Every conflict behind the figures on this page. All rulings.

Settled

1971 total production

Our ruling: The difference is exactly the 1,806 Boss 351s. We show 151,484 including the Boss 351, and 149,678 without it.

What each source says (2)

Sources

  1. 1971 Ford Mustang Fact Sheet Over-Drive Magazine · read 2026-10-11
  2. 1971 Ford Mustang Boss 351 MustangSpecs · read 2026-10-11
  3. 1972 Ford Mustang Fact Sheet Over-Drive Magazine · read 2026-10-11
  4. Ford Mustang (first generation) Wikipedia · read 2026-10-10
  5. 1971 vs 1972 vs 1973 Ford Mustang CJ Pony Parts · read 2026-10-11
  6. 1971 Mustang Technical Data Maine Mustang · read 2026-10-10
  7. 1971 Ford Mustang Production Numbers MustangSpecs · read 2026-10-10

Year by year

The Boss 351 in each model year.

1971Ford MustangThe biggest first-generation Mustang, and the year the Mach 1 made up almost a quarter of production.151,484 built