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copbait73 copbait73 is offline
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Join Date: Nov 2003
Location: Chesterfield IN
Posts: 1,316
I bought my first MFI car, a 72 911T years ago. The owner sold cheap because he was told the "prohibitively expensive" MFI was defective and needed replacement. He was done with Porsches and their expensive upkeep.

I got the car home and tried a typical for the time Unisyn but immediately noticed the RPM dropped so logic said this won't work.

Working in a lab at the time I rigged up a manometer and metered stopper like the manual showed and successfully adjusted the air by-pass. I sold the car to a friend and the rig went with the car.

Another on this thread commented his ITBs needed adjusting every 1,000 miles. I found the same on my MFI (1500 miles) however it became a ritual and cost me nothing but a few minutes once a month.

I have several of the synchronizing tools above, used them on PMOs. They are better than the old Unisyn however the method of operation may have the same drawbacks as the old Unisyn when used on a Porsche TBI.
Old 01-27-2010, 07:42 AM
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