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Jeff Alton Jeff Alton is offline
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Join Date: Jan 2003
Location: Langley,B.C.
Posts: 10,148
My motor is NA but it may give some help for you. Off throttle down hill (big vacuum) I will 20:1 AFR's. I run 40PSI constant. When the tuning was still only roughed in at idle I had 10.5:1AFR and it was not smoking, it would smell rich, but no smoke. IF you are seeing black smoke at idle, it is reallllllllllllly rich!

Turn3 Autosport- Full Service and Race Prep
997 S 4.0, Cayman S 3.8, Boxster 2.7, Boxster S race car, 996, 955 Cayenne TT, 958 Cayenne TT
Old 03-18-2008, 04:25 PM
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