The initial 16 psi of boost was deemed to be too much for longevity—and too much power for the stock block—so the superchargers were underdriven to put out 10 psi, which was still good for 850 hp at 6,800 rpm. That might still seem high winding for an FE, but the rotating assembly was prepped to spin 7,400 rpm. “We had to spin it up a little,” Jim said. “Those tunnel-port heads aren’t really happy until 6,000 rpm anyway.”