In 1965, my '62 409 engine had 0.030-inch oversize 12.5:1 compression pistons, an Isky then Erson camshaft, Mondello ported heads, Du-Coil ignition with new space-age spark amplifier. Doug's tri-Y headers, 15-pound aluminum flywheel. E&R rubber disc clutch assembly and smaller metering rods in both AFBs. At 115 mph, the tach read 6,300- 6,400 rpm in the traps with 4.88:1 gears and 12x27x15 slicks. racers with questionable cubic-inch engines.