Why Mustang Fans Are Still Salty: Boss 351 Beats 429 Cobra Jet in 1971 Test
Bottom line: In Motor Trend’s 1971 straight‑line test the Boss 351 Mustang posted a faster quarter‑mile time than the larger 429 Cobra Jet, and the result still fuels debate among enthusiasts.
Why Mustang Fans Are Still Salty: Boss 351 Beats 429 Cobra Jet in 1971 Test
Image: Why Mustang Fans Are Still Salty: Boss 351 Beats 429 Cobra Jet in 1971 Test – Performance Comparison and Specifications
Design & Looks
Both cars share the 1971 fastback body, but the Boss 351 wears a subtle “Boss” badge, a dual‑tone stripe and a hood scoop that hints at its high‑revving V8. The 429 Cobra Jet looks more aggressive with its “Cobra Jet” badging, a larger scoop and a beefier front grille. The visual cues tell you which engine the car carries, and fans often pick sides based on style as much as speed.
Performance & Mileage
The Boss 351 packs a 351‑cubic‑inch (5.8 L) 2‑V V8 that makes about 300 hp at 6,500 rpm. Its lighter crank and higher rev limit let it launch quicker, which is why Motor Trend recorded a 13.8‑second quarter‑mile. The 429 Cobra Jet, a 429‑cubic‑inch (7.0 L) 2‑V V8, claims 370 hp, but its heavier rotating assembly and lower redline keep the 0‑60 time around 7.3 seconds in the same test. Mileage tells a similar story: the Boss averages roughly 13 mpg city/18 mpg highway, while the 429 drops to about 10 mpg city/14 mpg highway.
Price & Rivals
When new, the Boss 351 sold for about $4,500, a modest premium over the base Mustang. The 429 Cobra Jet cost roughly $5,500, reflecting its bigger engine and higher performance promise. Today, collectors pay $40‑$60 k for a well‑kept Boss 351 and $70‑$100 k for a Cobra Jet, depending on originality and mileage. Their rivals at the time were the Chevrolet Camaro Z28 (350 ci) and the Pontiac Firebird Trans Am (455 ci), both offering similar power battles.
| Engine | Mileage (city/hwy) | Original Price (USD) | Top Features |
|---|---|---|---|
| 351 cubic‑inch (5.8 L) 2‑V V8 – Boss 351 | 13 / 18 mpg | $4,500 |
|
| 429 cubic‑inch (7.0 L) 2‑V V8 – Cobra Jet | 10 / 14 mpg | $5,500 |
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FAQ
- What was the quarter‑mile time for the Boss 351? Motor Trend recorded 13.8 seconds, slightly quicker than the 429 Cobra Jet’s 14.2 seconds.
- Is the Boss 351 worth buying today? For collectors who value rev‑happiness and a lower price tag, the Boss 351 offers strong appreciation potential and easier maintenance.
- How does the 429 Cobra Jet’s fuel economy compare? The Cobra Jet averages about 10 mpg city and 14 mpg highway, lower than the Boss 351’s 13/18 mpg.
What’s your take? Share your thoughts in the comments below.
Source: Read Official News
