[cobrarkc]

The real problem with the open chamber design is that even though it will give you lower compression it will actual cause more detonation than the closed chamber ones. The Aussie 2v heads are a better choice, they have the smaller ports and valves for low end torque and the more efficient quench chamber. The 4v heads on a cobras motor will make plenty of torque because you don't have to push an extra 1000lbs. around it's more of a factor in a Mustang or larger car. You can always stroke the motor to make better use of the 4v ports