The way I understand it is that the smaller the port the higher the velocity for better low end torque. The bigger port would allow more volume at the expense of velocity but higher flow at higher rpm's. Any other opinions? Andy 79 80 rocco's -- To subscribe or unsubscribe, send email to scirocco-L-request@privateI.com, with your request (subscribe, unsubscribe) in the BODY of the message.