Tbitz EFI is an excellent cost effective alternative and has worked very well in my 80SC since the install late 2008. If you have any issues with the CIS I recommend to have a look at it. Actually I recommend it to anyone with a CIS equipped 911, even those with a well functioning CIS. The tbitz system comes mapped for a standard SC and works right out of the box. Install is a nice weekend job, or one longish Saturday if you get help from someone who knows 911 and Megasquirt. It comes with a an easy to follow step by step installation manual illustrated with pictures. After the install you will have increased driveability and throttle response as well as an easy to maintain fuelling system.
