checked the compression on my #s 69 roadrunner. compression #s warm were 148 to 159.Is this in tolerance? The motor is stock never out of the car.The stock heat riser is still on the car.Oil preessure is fine doesnt smoke runs and drives like it should.The only problem is when you rev the motor up the rpms are slow to come back down . I am getting ready to pull motor to do engine bay and would like to address any problems at that time i do not want to hurt #s motor any help ? thanks