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rfmaster · 07-03-2009, 10:34 PM

OK on fuel pressure - it may be worth checking with another gauge just be sure. The pinging that you are describing maybe due to re-formulated gas (E10). E10 has stoich mixture at 14.3 vs. 14.7 for normal gasoline formulation. It does not take that much but a persistent lean condition with E10 is a common problem for early EFI systems. Knock sensor is working over time in your case taking out timing when you really needed. Hence, sluggish throttle response.

Which software are you running WinALDL, Tuner-PRO?? Can you capture data logs? I wonder what your cross counts look like and BLM's - my guess they are all well above 128-132 region.

//RF

07-03-2009, 10:34 PM	#10
rfmaster Registered User Join Date: Oct 2003 Location: OC CA Posts: 1,374	Re: 87 running lean? OK on fuel pressure - it may be worth checking with another gauge just be sure. The pinging that you are describing maybe due to re-formulated gas (E10). E10 has stoich mixture at 14.3 vs. 14.7 for normal gasoline formulation. It does not take that much but a persistent lean condition with E10 is a common problem for early EFI systems. Knock sensor is working over time in your case taking out timing when you really needed. Hence, sluggish throttle response. Which software are you running WinALDL, Tuner-PRO?? Can you capture data logs? I wonder what your cross counts look like and BLM's - my guess they are all well above 128-132 region. //RF __________________ "The Beast" 1975 Chevrolet C20 longbed 350/700R4! with 3inch body lift Dual Flowmasters Super 40's! TBI retrofit completed (2007-07-29) New 383CID (+030) 08-304-8 9.5:1CR x36,005 (2012-12-17)