'69 Mach I
'70 Boss 429
'70 Mach I
History of Mustang Performance |
| The Muscle Cars |
The Mustang grew by another 4 inches. Mustang engines were a 200 C.I. six cylinder, a 302, 351, 390 and 428 V8’s. The small block 351 Windsor was based on the 289/302 block. In 1970 the small block 351 Cleveland became available. The 390, 428 (and the 427) all were from Ford's big block.
The Mach 1 was introduced and offered with the 351, 390 or 428, a stiffer suspension and was offered only as the Sportsroof (fastback). Manual drum brakes were standard with power front discs available. The 351 Mach 1's were the most popular by far with the 390 being the rarest because it didn't cost much more to step up to a lot more power with the 428.
Limited production Boss 302’s and 429’s were offered to the public in the 1969 and '70 model years. Built to be professionally raced the Boss 302 was very successful in the Trans Am series. The Boss 429 was built for Nascar, but that engine was never raced there in a Mustang. Less than 9,000 Boss 302's were produced. The '70 Boss 302 sold for $4100. About 1,300 Boss 429's were produced at $5100 each.
| Related Events | 1969 | As Shelby loses control to Ford executives of his Shelby Mustang he asks Iacocca to quit using his name. |
| 1969-73 were the worse years for US auto-releated fatalities with about 55,000 killed each year. | ||
| 1970 | Clean Air Act passed by Congress giving the Federal Government the authority to regulate vehicle emissions. | |
| Imports are 14% of U.S. sales | ||
| Average new car has a top speed of 125 MPH & gets 12 MPG | ||
| '69 Mach I |
'70 Boss 429 |
'70 Mach I |
| V8
Engine Displacement (cubic inches) |
Intake | SAE
Gross Horsepower |
| '69 | ||
| 302 | 2 bbl | 220 |
| (Boss) 302 | 4 bbl | 290 |
| 351 | 2 bbl | 250 |
| 351 | 4 bbl | 290 |
| 390 | 4 bbl | 320 |
| 428 | 4 bbl | 335 |
| (Boss) 429 | 4 bbl | 375 |
| '70 | ||
| 302 | 2 bbl | 220 |
| (Boss) 302 | 4 bbl | 290 |
| 351 | 2 bbl | 250 |
| 351 | 4 bbl | 300 |
| 428 | 4 bbl | 335 |
| (Boss) 429 | 4 bbl | 375 |
The Mustang was
built on the larger Fairmont/Torino platform. Ford was planning for the big block
V8's just before the fuel crisis and emission requirements hit. These cars grew by
another 3 inches and were big "luxury" Mustangs and didn’t handle as well
as in previous years.
The ’71’s offered the same engines as before, but as smog and fuel
efficiency restrictions came into play the power started dropping. The V8's lost HP in '71
and again in '72. New bumper requirements in '73 added weight--up to about 3800
lbs. In '72 Ford began using Net HP ratings instead of Gross.
The Boss 351 was one of Ford's best small-block production engines, arguably the best
until the 4.6L DOHC. 1,700 produced.
| Related Events | 1973 | OPEC cuts oil supplies to countries friendly to Israel in the 1973 Arab-Israeli War. |
| Before the Oil Crisis the average price of gasoline was $.40 or about $1.20 in today's dollars. Prices jumped after the OPEC embargo and rose steadily until 1981. | ||
| 9.7 million American-built cars sold. Still the record. | ||
 '71 Boss 351 |
 '73 SportsRoof |
| V8
Engine Displacement (cubic inches) |
Intake | '71 SAE
Gross Horsepower |
'72 SAE
Net Horsepower |
'73 SAE
Net Horsepower |
| 302 | 2 bbl | 210 | 141 | 141 |
| 351 | 2 bbl | 240 | 177 | 177 |
| 351 | 4 bbl | 285 | 266 | 266 |
| 351 | 4 bbl | 330 | 275 | n/a |
| 429 | 4 bbl | 370 | n/a | n/a |
On to 1974-78 The Economy Years
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Page last modified on 10/22/00