Datsun510zen
The 510 was designed specifically around the highest power to weight ratio possible. In race trim the BRE 510s were 185hp and 1700lbs 9.2lbs per hp. Seeing lightness as a mark of poor quality is a fools miss-perspective, because it's totally missing what makes this car perform the way it does. Hot Rodders have known for decades, the lighter it is the faster it goes. It also has close to perfect 50/50 weight distribution, a very low center of gravity, and a semi trailing arm independent rear suspension.
This allowed it to accelerate out of corners much earlier than the Alfa and the BMW. Set up right, once you hit the apex of a corner, you can hit the gas, let go of the steering wheel and the 510 will launch out of a corner like it's found a new gear. In tight corners you can see the Alfa's inside rear tire lifts 4" off the ground. On three wheels, you have to wait until you're out of the corner to begin accelerating hard. By then the 510 has pulled ahead and you are playing catchup from one corner to the next.
The advantages of a smaller 1.6L vs the 2.0L combined with the lighter over all weight, and lower center of gravity meant better fuel milage, better handling, faster acceleration, and higher revving 9K+ rpm giving it a broader power range that evened out any top speed advantage of a bigger 2.0L motor.