crossover or x-pipe

T-N-T said
Back in the late 80's the '71 340 4 speed 'Cuda I had ran 12.5's on street tires with a mechanical tach drive Mallory dual point, a .509 cam, 2.5" dual with generic turbo mufflers and a thermoquad with an adapter on a Tarantula intake. It ran a flex fan and never overheated.

It worked for me... View attachment 1714990088

Yup, and I see many 408's out there, with the RPM air gap, Holley carb, MSD junk blah blah blah that run the same or not much better. And you did it with street tires that are nothing like we have today.