Most underrated sleeper motor from Ford?

Most underrated sleeper motor from Ford?

The Boss 351 in a big ole flat back '71 Mustang smoked most of the big blocks of the era- 428's and 429's included. The 427 was probably more bad ***-- but everyone knew about those. I believe a common ET for the era was in the mid to high 13's. A quote from the article below says that the Boss 351 made the Z28 look like a gas mileage motor! Lol

Everyone also knows about the Boss 302- but a lot fewer people have the same respect for the hypo 289 which was a sort of kissin cousin that could easily rev to 8000. I have first hand experience with both motors-- they really sing!

IMO, the 428 Cobra Jet… Factory rated at 335 horsepower. A well built one will dyno around 405-410 HP with beastly torque.