PerTronix's Flame-Thrower Street/Strip HEI distributors will produce 67 percent more energy in the coil, and deliver twice the energy across the spark gap. Plus, they deliver misfire-free performance up to a minimum of 7,500 rpm, a 3,000 rpm improvement over most original HEIs. Each distributor uses a new aluminum housing, cast and machined from a strong but lightweight A384 alloy. High-quality bronze sintered bushings are installed, aligned, and bored for accuracy and extended mileage use. Features include an adjustable vacuum advance, a high-performance mechanical curve kit, aluminum housing, a high dielectric strength cap with solid brass terminals, a balanced rotor, and a centerless-ground shaft.