early engine spec question
05-16-2007, 11:54 AM
#2
Rennlist Member
CIS:
Super-mild cams
CIS Injection
Special shaped piston domes
911S (carb or MFI):
High lift, relatively radical cams
Carbs or Mechanical Fuel Injection
Conventional high dome pistons with valve reliefs
Many other differences also exist, because with the introduction of CIS we moved into the world of pollution control. Displacement increases allowed Porsche to maintain a performance edge, which also gave the CIS engines a wider power band that occurred lower in the rev range.
Super-mild cams
CIS Injection
Special shaped piston domes
911S (carb or MFI):
High lift, relatively radical cams
Carbs or Mechanical Fuel Injection
Conventional high dome pistons with valve reliefs
Many other differences also exist, because with the introduction of CIS we moved into the world of pollution control. Displacement increases allowed Porsche to maintain a performance edge, which also gave the CIS engines a wider power band that occurred lower in the rev range.