This old NASCAR engine sat for 20 years, and the dyno showed the engine only made 477 HP. Without increasing the displacement, changing the block, heads, crank, rods and manifold, we rebuilt the engine with new pistons, rings and valve train. NHRA Champion Greg Anderson honed the block, and Dennis Borem from ProMotor Engines put it back together. Let's find out how much this Yates headed Ford makes now!