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patkeefe patkeefe is offline
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Join Date: Apr 2004
Location: Bradenton, FL
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I am likely going to change my SC turbo to Megasquirt II, maybe next year. I have found over the years that it is not so simple to effectively double the HP output of a N/A system by simply trying to imitate a 930 setup, although I almost have it figured out.

Fundamantally, there are really no differences in the K-Jet and the more advanced electronic systems. It seems to me that the CIS is a bit more stone age with regard to tuning. The Bosch engineers built the CIS system to get away from carbs, which allowed more easy compliance to environmental regulations. However, the K-Jetronic is both technically advanced for something designed over 40 years ago, and elegant in its simplicity from a tuning standpoint.

The main differences in between CIS and any of the other systems are simple to see:
All of the modern tuning parameters were BUILT IN to the hardware of the CIS system. For instance, the shape of the air cone matters, as I believe that is what provides the idle and enrichment characteristic of the particular setup. This is done by some sort of tuning tweaks in the EFI systems. It is theoretically much easier to change parameters in an EFI system than in a K-Jetronic system. There are some interesting and comprehensive discussions on this board regarding this topic. Relationships between the WUR and FD seem simple, because the factory MATCHED these characteristics for each particular engine setup type.

I suppose when you have a CIS system, and get the car shaken out fairly well, there is absolutely no need to go any further. If you want to continue to tinker and try and wring out that last 3 HP, go ahead. There is always going to be the CIS camp and the EFI camp.
Patrick E. Keefe
78 SC
Old 11-18-2014, 09:59 AM
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