Hard question to answer, son n laws 440 Charger, he's young and motivated to build that Go fast Car!, Which I was there once too. He likes the originality of the restoration look, and basically is willing to plug up the pipe a little, probably following me a bit as I have gotten back to the originality of my car for the shows and have told him about the evils of that dreaded exhaust leaking header.....The engine we built has a lower compression, and by using the smaller 75cc heads on the E streets we are raising it to 10. or real close,