The Golden Age of muscle cars in the late-60's and early-70's witnessed automobiles with some of Detroit's wildest designs and highest horsepower engines marauding the nation's highways and back roads. In an effort to differentiate themselves from competitor's offerings, each manufacturer created special versions in a variety of body styles from the mild to the wild. There was the Pontiac GTO, Chevrolet Camaro, Dodge Challenger, Buick GS, Oldsmobile 442, Mercury Cyclone, and AMC AMX.

Perhaps none were more famous than Ford's Boss series of high performance Mustangs offered from 1969 to 1971. They were in purpose and design bare bones muscle cars in the pony car segment with a premium placed on handling, power and aggressive styling. With engine options ranging from a diminutive but stout high revving 302 to the mid range intermediate block 351 and on up to the NASCAR based 429 "Shotgun," they were and are some of the most desirable muscle cars ever produced.

Let's check out the history of this trio and what makes each of them so special in the annals of muscle cardom.

Boss 302

1969 Ford Mustang Boss 302
via Mecum

The Mustang Boss 302 was offered during the 1969 and 1970 model years and came out of an effort to compete in Trans Am racing. With ex-GM "Boss" Bunkie Knudsen on board - get it, "Boss"? - he directed Larry Shinoda to design and build a car to not only rev up sales of the street Mustang but homologate the car for the racing.

The design that Shinoda came up with was crisp and clean and without the obligatory adornments that most muscle cars of the time were festooned with. She was fitted with Ford's 302 block with high performance Cleveland heads that would later go on the Boss 351 engine.

They were only offered with 4-speed Toploader manual transmission, as were all Boss cars ever made, along with a competition suspension system, front disc brakes, manual steering, and a beefy 9 inch rear. Horsepower was estimated at 290 at 5,800 rpm and 290 lb.-ft. of torque at 4,300 rpm. She could scoot to 60 mph in 8 seconds and displayed great finesse in the handling department. List price was a quite reasonable $3,500 and change.

RELATED: The Forgotten BOSS: The 1971 BOSS 351 Mustang

Boss 429

1969 Ford Mustang Boss 429 Classic Recreations
via Classic Recreations

Next up is the Boss 429, which hardly needs an introduction. Where the 302 was known for poise and control on the road and rampaging around Trans Am circuits, the 429 was created for the high banks of Daytona. The Boss 9, Semi-Hemi, or Shotgun motor was Ford's answer to the Dodge 426 Hemi engine and she needed to produce road going versions of the engine for use in NASCAR. And thus was born the Boss 429.

The cars came off the Ford assembly line as bare bones Mustang fastbacks before being transported over to Kar Kraft who took care of the modifications necessary to fit the mammoth "Shotgun" in the engine bay. Distinguishing itself from the 302 is a massive hood scoop controlled by a lever in the cockpit. Graphics are subdue displaying the "Boss 429" logo. The rest of the car was set up similarly to the 302 albeit with the shock tower mods and dropped stance. And while you might think the car would be a beast on the street, the heads and cam phasing were all wrong making it rather ungainly and ill-responsive as a stop light warrior. Thankfully, modern day iterations by Jon Kaase have eliminated those problems allowing the Boss 9 to finally live up to its potential/

Boss 351

1971 Ford Mustang Boss 351
Mecum Auctions

And last up is the 1971 Mustang Boss 351. Not only did this car appear for a single year, but she replaced both models. And with only 1,806 examples produced she is just about as rare as the 1,300 some odd 429's made and considerable more scarce than the prolific number of 302's.

Fitting right in between the 1969-70 302 and 429, the 351 engine had all the high revving benefits of a small block with the more generous torque of a larger cubed engine. The body style also changed which was larger in just about every dimension. Some, however, contend that this Boss was the best of the lot with better handling via the staggered shock setup and perhaps the best small block engine ever made. Her 3.91 equipped Traction-Lok rear enabled her to best both her stablemates in contemporary drag and road tests.

Is A New Boss On the Horizon?

And it appears that a new Boss 429 might be on the horizon. With the introduction of the Super Duty series "Godzilla" engine, the Mustang might just benefit from a warmed over version going in to the Mustang. Details are sketchy at this point but with the Mustang being the last car in Ford's stable, they just might offer something hearkening back to their racing past. Stay tuned and buckle up.

Sources: Ford, Mustangs and Fords, Motor Trend

NEXT: 15 Things You Forgot About The 1969 Mustang Boss 429