Thread: EFI Tuning

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Jerry,
Tell Corey 'Thanks' for the F/A guidelines. After getting my spark map sorted out with Edelbrock I put my wide band back on and went out for some test runs with laptop in hand. Everything was good up into mid-range, but as I passed 4000 to 4500rpm at WOT I got some pretty severe exhaust 'pop'. With a new confidence level in the spark map I concentrated on the F/A indicator, and what I saw was mid-12's from 1800rpm up past 3500rpm, but then as it got into the peak power area the numbers went into the mid to high 13's, or maybe low 14's - not enough to trigger my "Lean" LED on the Edelbrock Handheld Calibrator (it was not truly Lean with a 14.7 reference point), but it was more lean than desired. I cranked in more fuel at the top end from 3000 to 7000 rpm (6000 rev limiter), and from 26" up to 31"MAP - ended up with 28% more pulse width at the top than it had before! It now pulls strong through the power band, and the torque is scary high I've not had it on an extended highway cruise, but in 4th at 45mph it's at cruise 2000rpm and it homes in on 14.5 to 14.8 F/A which is perfect for closed loop. I appreciate the help

The Handheld Calibrator unit is a pretty powerful tool. Once the base maps are set up to your satisfaction if you're on a trip and cannot get 91octane, no corn fuel it is a very simple matter to do a 'Global Timing' adjustment and back out a couple of degrees across the board, or only at the top. Once you get back into better fuel you can simply back out the over-writing "correction" in the calibrator, returning to your base maps. Pretty sweet!!