1970 Mustang Engine Information – 428 cubic inch V-8 (7.0 L Boss V8)

429 Boss V8

The Boss 429 engine was offered late in 1969 and was rated at over 370 horsepower. It had aluminum heads with extremely large free flowing ports, contoured exhaust manifolds, a high rise intake manifold to help it gain horses.

The block was a strengthened 429 cast block. They had HP429 cast into the front left side of the block. The 4 bold main engine had forged crank and connecting rods. The first 279 (model (820-S) engines used NASCAR type connecting rods, the remainder of the engines (model 82-T) used beefed up production type rods.