Super Cobra Jet 1969 Tank Top

The 429 was NOT simply a 1 (or 2) cubic inch larger version of the blue oval 427 & 428 engines. It was a totally new engine from a different engine family. This design was a departure from the paradigm, utilizing thin-wall casting methods and a skirtless block to reduce weight. The Super Cobra Jet, rated at 375 HP, had a 4-bolt main block, a Holley 780 cfm 4BBL carburetor, and a larger mechanical camshaft. It was only available with a 3.91 or 4.30 rear axle ratio. In 1971, the CJ engine also used a 4-bolt main block. However, these engines were actually derated and produced power in the 440–460 HP range. This was done to deceive insurance companies (common practice in that era), so that buyers did not have to pay higher insurance rates.