i had less than 75 runs on it it was filled to the lower water pump hole i never sonic tested it i gues it was making abot 880 it went 7.81 in my Daytona with a clutch and lenco. the cylinder walls got out of round and the car slowed up bigtime. i said to myself no more stock blocks so i built the Pso it only has 34 eighth mile hits and about 6 quarter mile hits