The Boss 302 looked much flashier with its unique stripes and the availablity of the shaker hoodscoop. (I don't like the looks of any Boss 302 without the shaker - the hood looks too naked and missing its best part.) But the Boss 429 is the biggest and baddest.
The '69 Boss 429 had its large hoodscoop painted like the rest of the car. The paint didn't adhere well to the scoop material and often flaked off. They made the '70 Boss 429 scoop black to avoid this problem. The black hoodscoop looks okay (I certainly wouldn't refuse a '70 Boss 429 if someone wanted to give me one), but not as good as the '69. And you want one of the earlier '69 Boss 429s to get the better heads and valve covers, as I recall.
My buddy Mark would probably select the '71 Boss 351. He had one back in the mid-seventies but had to sell it for financial reasons. Its the one former car of his he would like to have back (us older guys all have at least one of those). The Boss 351 motor is exceptional. It has huge canted valves (like putting Chevy big block heads on a small block V8) and was based on the 351 Cleveland (far superior to the cheaper and more widely available 351 Windsor). Mark likes it so much that he has a stroked 351 Cleveland in the Factory 5 Racing Cobra roadster kit car he built and has another 351 Cleveland (with the rare Nascar heads and Bud Moore manifold) for the '72 Pantera he is currently restoring.
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2008 Shelby GT500 torch red with black stripes + sequentials
2001 Cobra mineral grey with 2003 Mach 1 shaker hood
1996 Cobra color-shifting mystic paint + sequentials
'69 Boss 429!
I love the looks and also love the 429
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2008 Grabber Orange GT premium, 5 speed manual, 3.31s
Diablosport Predator Tuner and Bamachips tunes (93 Race, Torque, and Preformance), Boom Tubes
Kooks LT headers and catted H pipe, Steeda UDPs, delete plates, UCAs, LCAs, and Panhard brace, all waiting on time to install them
Gotta say the Boss 302. Sure straight line speed is fun, but corner carving is my favorite. Having a street legal Trans Am car that screams at the top end is what I consider a good time.
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Proud owner of a '65 289 coupe w/ C4. Equipped with Edelbrock Performer intake K&N air filter, and 600 cfm carb, Comp Cams Xtreme Energy valvetrain, Comp Cams XE262H cam, MSD ignition, and ported heads. Suspended by 600# 1" drop front and stock rear springs, KYB shocks, 1" front and 7/8" rear sway bars, and Traction Master style traction bars. Your friendly suspension kid.
I'm a big block kinda guy, therefore, the Boss-9. There's just something about cramming that huge engine with those fabulous heads into a sportsroof. My favorite year is the 1969. There's absolutely nothing wrong with a Boss 302, very strong runner and better handling. As for the Boss 351, I like the engine alot, better than the Boss 302, but I have never been as fond of the larger bodystyle.
Favorite Boss 
