The 1973 production year marked the end of the legendary generation of the Ford Mustang. The high performance engines were almost a thing of the past as they decreased in availability. 1973 was also the last year of the Mustang convertible until they were resurrected in 1983. The era of the classic Mustang drew to a close, leaving behind a rich history while the Mustang II debuted in 1974.

The first generation of the pony car ended.

Emissions regulations really began to cramp Ford’s style as it throttled output and performance. Power ratings dropped even further as the 302 plummeted to a mere 135 horsepower and the two 351s that were left (the renowned Windsor and two barrel Cleveland) were whittled down to just a little over 150 horsepower each.

In an effort to keep with the changing times, Ford began to rethink the Mustang and 1973 was the last year to see the classic muscle car. At its prime, the Mustang was powerful and sleek, the be all, end all pony car.

The 1972 Mustang lost more power with the elimination of the Boss 351. This left the Mach 1 as the Mustang’s only performance vehicle. This marked the end of the classic Mustang era.

In an effort to reduce emissions and comply with Federal regulations, the compression ratios were lowered. The 429s were gone along with the Boss 351.

Except for the changes in lowering performance, the Mustang did not undergo any real changes. For the first time in the Mustang’s history, the front grille went unchanged. As a testament to the changing times and the shift from performance muscle car to more of a luxury vehicle, the standard hardtop was the best selling model for the year. The top option in engines was the 351 Cleveland, sporting 275 bhp.

As the once sleek, sporty little Mustang moved into the new era, sales began to slump. In 1972, sales were at their lowest since the Mustang’s unveiling slumping at 111,015.

The 1971 production year marked some significant changes for the Ford Mustang. For many collectors and enthusiasts, this marked the end of an era for the Mustang. The age of total performance cars slowly began to draw to a close as smog and fuel efficiency restrictions were enacted.

This was also the time known for the “big” Mustangs. They grew to “massive” proportions, adding 2.1 inches to the length, 2.8 inches to the width and 1 inch to the wheelbase. They also increased by about 100 pounds. Built on the Fairmont/Torino platform, these Mustangs were introduced as luxury Mustangs. Their bulk, however, did not allow them to handle as well as their smaller ancestors.

The Boss 302 and Boss 429 models also fell to the wayside and the 351 rose to the top even though it was taken from 300 bhp down to 285 bhp. However, the Mach 1 and the Boss 351 hailed as the Mustang’s performance cars.