Accel DFI 7

[Pete100]

Well I have my dfi7 installed on my 73 Corvette - a real fun job trying to shoe horn all the wires and fuel lines and throttle body into zero available space and now I have been looking over the programming of the ecm. I have a wide band to capture data but it looks like everything starts with the numbers I plug into air fuel ratio table. All the various instructions available tell me modify the VE table until the numbers in the air fuel table are met.
My question is how do I verify that the air fuel ratios I initially place in the cells in the table are the best for the engine? How do I know if they are wrong, what to correct them too?
The rule of thumb I have found is 14:1 at idle and 13:1 at wot. Is their any systematic way to go about finding the best numbers at the various pressures and rpms?
Pete

[Hammered]

The initial tune based on the engine specs will likely be VERY rich. Set your AF table to 14.7:1 everywhere except the bottom couple rows which represent WOT. You should set those to 12.5:1 to 13.5:1. Focus on setting the VE table at idle and cruise first to get to where the ECM is pulling 2-4% fuel out (i.e., slightly rich). Once you have VE set, bump the timing up at different speeds until you sense knocking and then set the timing back a degree or two. Once you have this done, adjust the AF at idle for best idle and slowly lean out at various cruise speeds until the engine misses and then richen a few tenths. After this cycle, repeat the VE, timing and AF to refine it further. WOT needs to be similarly tuned by logging drag runs or tuning on a dyno. After all this, the Gen7 has some other parameters that may or may not need adjusting, but don't fool with those until the above is accomplished. I'm very happy with mine which was 100% tuned by me. See here for more info: http://1967firebird.atwebpages.com/efi2.php

[Pete100]

The initial tune based on the engine specs will likely be VERY rich. Set your AF table to 14.7:1 everywhere except the bottom couple rows which represent WOT. You should set those to 12.5:1 to 13.5:1. Focus on setting the VE table at idle and cruise first to get to where the ECM is pulling 2-4% fuel out (i.e., slightly rich). Once you have VE set, bump the timing up at different speeds until you sense knocking and then set the timing back a degree or two. Once you have this done, adjust the AF at idle for best idle and slowly lean out at various cruise speeds until the engine misses and then richen a few tenths. After this cycle, repeat the VE, timing and AF to refine it further. WOT needs to be similarly tuned by logging drag runs or tuning on a dyno. After all this, the Gen7 has some other parameters that may or may not need adjusting, but don't fool with those until the above is accomplished. I'm very happy with mine which was 100% tuned by me. See here for more info: http://1967firebird.atwebpages.com/efi2.php

Thanks Makes sense
Pete