1973 Mustang Mach 1 Fastback


The “big” Mustang or the “last of the Mustangs” is a car gaining ground with collectors. This was the third iteration on the original Mustang theme and some people felt it ventured too far from the original formula. The original 1964 1/2 Mustang was a sporty compact car (for the time) with sensational European influenced sports car styling. The car was a huge sales success from the start and could be optioned several different ways to please its buyers. Initially the car wasn’t the muscle car as it’s thought of today. This changed however with the hi po 289, the Shelby GT35o and a couple years later the Mustang had real competition to keep pace with -the General Motors copy of the Mustang, Camaro. Ever since, the two have had one of the hottest rivalries in the car business.


In 1967 the Mustang got refreshed styling and the option of big block 390 power. In 1969, Mustang got sleeker, muscle bound styling and some fire breathing 428 and 429 Boss V8’s could be ordered. Every time the Mustang was redesigned the body grew a little bigger. When the new 1971 Mustang models came out they were the biggest yet with a large engine bay to easily accommodate big block engines. Sadly the car arrived during a very transitional time in the car business and some of the muscle was stifled in 1972 when big block engines were no longer available.


The body style featured here ran from 1971-1973. The 1971 model year actually had two of the hottest performing Mustangs from the factory- the Boss 351 and the 429 Cobra Jet or Super Cobra Jet big block. Both are capable of quarter mile times in the 13 second range. The 1972-73 models don’t have the fire breathing engines of ’71 but you could still get the 351 Cleveland in varying levels of horsepower. The hottest Cleveland produced around 250 net horsepower in 1973.


The 1973 Mustang featured here is the Mach 1, the performance model of the lineup. All Mach 1’s are the fastback roof style but not all fastback’s are Mach 1’s. In actuality the Mach 1 doesn’t give any performance advantage because the most powerful 351 engine could also be ordered in other Mustangs. There was also a notchback roof style and a convertible available. Even though some(old) guys call this the big Mustang, the car is positively dwarfed by a late model Mustang in height and width if not length as well. Also in weight.


If you have questions or comments about different Mustang body styles, models, options etc please leave a comment. I’ve summarized quite a bit as Mustang trivia runs deep and putting in everything relevant here isn’t possible.



Driving Impressions

This car is in fair aesthetic condition with a hammered repaint, lots of scratches, dents and bruises but looking at the striking lines of the body it doesn’t really matter. It’s low to the ground with a hood half the length of the car. The roof from the windshield to the trunk is nearly flat, the rear window almost horizontal. The Mach 1 ram air hood with twin air intakes looks tough. You can see the designers were emphasizing power and performance.


Grab the handle and the door springs open. You have to bend your body getting in and the roof is close to my head. The back window in the rear view mirror is a slit and you have to rely on the tiny side mirrors to back up. Let’s just say the rear visibility is bad. Crank over the 351 and after a few rotations it instantly lights sending a shock through the whole car. The body shivers as the Cleveland idles, sending a staccato booming out the 3 inch exhaust tips. Pop the floor shifter into reverse and the C4 transmission doesn’t respond for a moment then clunks into gear. Going forward now, everything is well with the engine pushing the car along happily. The ride is stiff and bouncy transmitting the road surface up through the seat. A small diameter aftermarket steering wheel gives vague but quick steering response. You have to make small minute corrections but being able to change directions quickly gives confidence.


Get on the gas and the 351 smoothly pulls the Mustang up through the revs with a angry ripping sound at high revs- the C4 automatic shifting unobtrusively. The trip to 60 taking about 7 seconds, maybe less if the engine likes the air and there isn’t too much wheel spin. The acceleration at the top of second gear is relentless, the exhaust bellows and you start to check your surroundings quickly! If you hit a bump in the road the front end bobs up and down and you seriously consider slowing down. During the drive you can smell unburnt hydrocarbons from the emissions untangled 351 Cleveland.

The test car has a 2v Cleveland with Edelbrock Performer Intake, Edelbrock carburetor, headers and 2 1/2″ dual exhaust. 


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