Steve, the Performer is a complete "turd" on a 455 build. I've tested them several times, dyno and on the street. Couldn't make track runs with one on my last 455 at 500hp because it was too restrictive. So much so that it induced a HUGE hesitation/stumble going from idle to full throttle with good traction. The engine was also "surging" in the mid-range so I stopped testing with it and put the iron intake back in place with no other changes and ALL the problems disappeared.
I'd also add that it's highly likely the one Jim Hand was testing was modified a bit, and may have had a spacer on it as well.
In any case a stock one with a port match to a stock Felpro intake gasket is a "turd" on a 455 much past 400hp so I recommend for folks to avoid it for higher HP builds........
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73 Ventura, SOLD 455, 3740lbs, 11.30's at 120mph, 1977 Pontiac Q-jet, HO intake, HEI, 10" converter, 3.42 gears, DOT's, 7.20's at 96mph and still WAY under the roll bar rule. Best ET to date 7.18 at 97MPH (1/8th mile),
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