I've seen stock eliminator cars stack spacers like that, maybe not 7 but a few anyway. Then the same car, 55 Chev, 265, 3 speed, set the national record for it's class in Acton Montana of all places. That was pretty damn cool!!
I bet 90% or more of the guys who make fun of 3/4 cams, pop up pistons, relieving, etc could never make a engine run back in the pioneering days of hot rodding. They would sit there wondering why nobody makes parts for these things.